Taking for granted that Jagr isn't in the same class as Gretzky, Lemieux and Orr, I'd start by comparing him to Howe, Hull, Beliveau and Esposito. There are a number of ways to analyze the data. I'm assuming you're talking specifically about regular season offense (ignoring playoffs and major international tournaments).
1. Vs X Scoring
In my opinion, this methodology is the single best metric for comparing players across different eras (assuming they're all first-line players, which is obviously the case here). This method posits that, after adjusting for outliers (like Gretzky/Lemieux) in accordance with a specific formula, offensive stats are adjusted relative to the era's top talent.
Using the seven year analysis, their results are (
source):
Rank|Player|Result
1|Gordie Howe |127.2
2|Phil Esposito |123.4
3|Jaromir Jagr |114.6
4|Jean Beliveau |108.9
5|Bobby Hull |107.1
2. Scoring ranking compared to Canadian players
This is an indirect method of taking into account the fact that Jagr played against a larger talent pool in a larger league. For those curious, there were no adjustments to any of the rankings for Howe, Beliveau, Hull or Esposito (let me know if I missed anything that should have been adjusted). Jagr's "Canadian only" rankings are as follows: 6th (1994), 1st (1995), 2nd (1996), 4th (1997), 1st (1998), 1st (1999), 1st (2000), 1st (2001), 3rd (2002), 8th (2003), 7th (2004), 2nd (2006), 7th (2007).
Player | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th | 9th | 10th
Howe | 6 | 1 | 5 | 3 | 5 | | | | 1 |
Esposito | 5 | 3 | | | | | 1 | | 1 |
Jagr | 5 | 2 | 1 | 1 | | 1 | 2 | 1 | |
Hull | 3 | 3 | | 1 | 1 | 1 | 1 | | 1 |
Beliveau | 1 | 2 | 4 | 1 | | 1 | | 2 | 1 |
Rankings
1. Howe: clearly in a class above the rest. He has more than twice as many top five finishes as any other player! Any way you analyze the data (Art Ross trophies, top three finishes, top ten finishes) Mr. Hockey is no worse than tied for first in any category.
2. Jagr: the great Czech fares very well according to this metric. He's second in number of top five and top ten finishes.
3. Esposito: surprisingly poor longevity (the fewest top ten rankings in the group), but I rank him ahead of the others because it's hard to overlook 8 top-twp finishes. We'll get to teammate context later.
4. Hull: very similar numbers to the great Hab, but gets the edge due to having a more dominating performance over his best years (6 top two finishes compared to 3).
5. Beliveau: see above.
3. Absolute peak
1. Howe - second only to Gretzky in number of Art Ross trophies. Won six scoring titles in total, three of which were by laughable 30% margins over the nearest non teammate.
2. Esposito - won five Art Ross trophies, four of them by a 10% margin and one of them by a 20% margin. If we exclude teammates (which usually makes sense but probably doesn't in this case, as I don't think Esposito was the main catalyst on those Bruin teams), the margins of victory are even larger.
3. Jagr - also won five Art Ross trophies. Comparing him to the closest Canadian in the scoring, he only won two of the trophies by more than a 10% margin.
4. Hull - although he won three Art Ross trophies, one was a tie and another was by a single point. He crushed the field in 1966 though (24% margin of victory).
5. Beliveau - clearly last; only one won Art Ross trophy, though it was a strong performance (11% over Howe).
4. Consistency of offense
I'm looking specifically at how consistent they were able to stay in the top ten in scoring.
1. Howe - nobody was more consistent than Mr. Hockey, with twenty consecutive seasons as a top five scorer. More than a decade after learning this fact, I'm still amazed.
2. Esposito - yes, he lacks longevity compared to the others (see next category) but during his peak, Esposito was first or second in scoring eight straight years. Nine consecutive seasons in the top ten.
3. Jagr - eight straight years in the top ten in a deep, talented league. Five straight years in the top five.
4. Hull - eight straight years in the top ten. Four straight years in the top five.
5. Beliveau - seven straight years in the top ten. Never more than three consecutive years as a top five scorer, though he did that twice.
5. Longevity
This really refers to longevity as an all-star calibre player. It's admirable what Jagr is doing this year, but I don't think that a 60 point season adds much to his legacy, even if it is at age 41.
1. Howe - see above. No player in hockey history was an all-star calibre player for as long as Howe. Was a top five scorer each year from ages 21 to 40. Truly mind-boggling. He almost makes Ray Bourque seem like a flash in the pan.
2. Beliveau - a top ten scorer from ages 23 to 39 (the year he retired).
3. Hull - tough to read; he could very well be third. A top ten scorer from ages 21 to 33, when he left for the WHA. Judging from his statistics and the estimated quality of the WHA, was likely a dominant scorer through age 36, perhaps even through age 39. May have had slightly better longevity than Beliveau, but the ties goes to the Hab due to less uncertainty about quality of competition.
4. Jagr - a top ten scorer from ages 21 to 34 (with one more very good, but not quite elite, offensive season on either side of that range). Jagr very well could have been second in this category, but the decision to leave the NHL really hurts him.
5. Esposito - he did not age well. Was only an elite (top ten) scorer between ages 22 and 32. Still a solid contributor through age 37 though.
6. Context - teammates
1. Jagr - Notwithstanding 2001, Lemieux's impact on the Czech is overstated. In his most dominant season, Jagr won the Art Ross playing with Martin Straka and German Titov. He nearly repeated the feat with Straka again, and Michael Nylander, in New York. He helped numerous teammates achieve career highs. At times he was truly a one-man show.
2. Hull - he won goal-scoring crowns and Art Ross trophies with shockingly weak linemates. Still, the presence of Mikita on the second line probably opened things up for Hull to an extent.
3. Howe - during his peak he played on a dominant team (with Kelly and Lindsay, among others) but his linemates were surprisingly mediocre for most of his career (especially since it was the Original Six era).
4. Beliveau - consistently played on some of the deepest and most talented teams ever.
5. Esposito - although the impact is sometimes overstated, the hulking Bruin is clearly the player most influenced by his teammates. Esposito probably would have won an Art Ross or two without Orr (he did so convincingly in 1969 before Orr became superhuman, and was runner-up the year before when Orr missed half the season), but I doubt he would have done so by such enormous margins.
7. Balance
In my opinion, players who can both score and set-up teammates are more valuable, on average, than players who specialize in one area.
1. Howe - versatility is another strong suit. Similar number of years as a leader in goals and assists, whether you're looking at top three (12-10), top five (14-17), or top ten (19-22).
2. Beliveau - very balanced. Seven years each in the top five in goals and assists. Similar to Jagr, but I give him the edge due to leading the league in goals and assists twice each.
3. Jagr - similar to Beliveau. Eight years as a top ten goal-scorer, ten years as a top-ten playmaker. (I'm using top ten as a proxy for being top five in a Canadian-only league). Never led the league in goals though.
4. Esposito - everyone views him as a lumbering goal-scorer, but he racked up a lot of assists. His numbers are quite similar to Beliveau (eight years in the top five in both goals and assists) but his high-end finishes (six times leading the NHL in goals compared to three times in assists) shows where Esposito's skillset truly lies.
5. Hull - clearly the most unbalanced player in the group. Twelve seasons in the top five in goals, just two seasons in the top five in assists. He was just as unbalanced (if not moreseo) in the WHA.
8. Context - role
Although we're specifically talking about offense, we need to consider if the players were used in a role that allowed them to maximize their offensive potential, or sacrifice their statistics for the good of the team.
1. Howe - on top of his incredible offensive consistency, he was a good defensive player (debatable whether "good" or "excellent").
2. Beliveau - very solid defensively. Probably as a good as Howe, but he had so much help from other teammates (particularly Harvey and H. Richard) that the edge goes to Howe.
3. Esposito - a big drop between Beliveau and the last three. Very few defensive responsibilities, though he did play on the penalty kill somewhat.
4. Hull - see above.
5. Jagr - all offense. Unlike the other four, received very little ice-time on the penalty kill.
9. Context - league
1. Jagr - played in the largest league with excellent integration of European talent.
2. Beliveau - spent a long time playing in the Original Six era. I give him the edge over Howe because the Red Wing was particularly dominant in the early 1950s, when the talent pool appeared to have been a bit weaker than the rest of the era; Beliveau debuted in 1954. The counter-argument is given that Beliveau spent his entire career on such dominant teams, so his opponents were less talented than the league average. A close call.
3. Howe - see above. Also note that he played a few years in the WHA. I won't hold that against him as his performance there has been ignored in my previous analysis.
4. Hull - peaked late in the Original Six era, but spent the second half of his career against weak competition (the recently-expanded NHL, and then the WHA). The reason I have Hull over Espo is because I've primarily ignored his time in the WHA in my analysis.
5. Esposito - played in the most watered-down era (peaked shortly after the NHL doubled in size, and many NHL calibre players were in a rival league).
10. Overall
Let's calculate a junk statistic (adding their ranking in each category). There are a few problems with this - it doesn't take into account how close the players are (i.e. are #3 and #4 virtually tied, or is there a clear break?), nor do I apply weightings to the categories. Still, I thought it would be an interesting summary:
1. Howe - 13 points
2. Jagr - 25 points
3. Esposito - 30 points
4. Beliveau - 32 points
5. Hull - 35 points
Howe is clearly the best of these five players and I'm surprised he wasn't moved into the "freak of nature" group with Gretzky, Lemieux and Orr. He may very well be the worst offensive talent out of those four, but he's closer to them than he is to the other mortals.
Based on the purely quantitative analysis, I have Jagr ranked 2nd (which would make him the 5th best offensive talent in NHL history). Subjectively, after taking into account the context, I think that this is a reasonable position. He has everything you could ask for - consistency, longevity, a dominating peak, and balance between goal-scoring and playmaking. All this was accomplished in a deep, integrated league, often as a one-man show.
Esposito is hard to read; on paper he's almost as good as Lemieux offensively, but there's a lot of teammate and era context that I've attempted to take into account. Beliveau and Hull round out the top five and aren't separated by much.
11. Other possibilities
Are there any other NHL players who were better than Jagr offensively?
Howie Morenz - the best offensive talent through the NHL's first three decades, but only won two Art Ross trophies.
Maurice Richard - a lot of positives, but very unbalanced and never won an Art Ross.
Stan Mikita - not quite as good as his teammate Hull, who is already behind Jagr.
Marcel Dionne - a lot of positives as well, but only two Art Ross trophies (pretending Gretzky never existed).
Guy Lafleur - six seasons of dominance, but absolutely nothing else.
Sidney Crosby - maybe one day, though injuries may have already permanently dented his legacy.
