Well I haven't heard another year mentioned since 1980. Personally, I think the Pens had as difficult as any road to the Cup in 2009 as any other team post 1980 Islanders. Post lockout the only team to come close was Anaheim. Even if Chicago wins I don't think it will have been tougher.
The Pens did it to themselves by having such a low seed that year but that resulted in them playing Philly first round who was the same team as ths year without Pronger. Washington in Round 2 who had the best high octane offense in the NHL and was outgunned by the Pens. Carolina was rather easy. But Detroit was the defending champs, they came back from 2-0 and beat them at home in Game 7 which hadn't been done in 38 years. Find me another team with a tougher road post 1980
Alrighty, grab a beer and we'll take a closer look at this.
Obviously it's a little subjective. Points/standing placements of opponents are important in determining it, but there's definitely a grey area. I personally don't consider the Washington team they beat that tough of an out. Much like this year, they were a team with exploitable weaknesses. Pittsburgh got away with poor team defense and suspect goaltending and won because Washington's was even worse. If you consider Pittsburgh's road to the Cup to be exceptionally tough, you must think highly of Washington. Not that there's anything wrong with that, but I would be in disagreement with that.
Overall, they had to beat the 9th, 4th, 11th, and 3rd place teams. I wouldn't say this is anything earth-shattering. Most champions get a first round opponent in the 13-16 overall range by virtue of a high finish, and this is really the only thing separating Pittsburgh from most others.
I would say the '95 Devils had a tougher road for sure, and of course finishing fifth had a lot to do with it. They beat the 1st, 3rd, 5th, and 6th overall teams in the league to win. Pro-rated to a full season, those teams had point totals of 97 (Boston), 104 (Pittsburgh), 103 (Philadelphia), and 120 (Detroit) in the pre-loser point era. It's pretty incredible that they went 16-4 against that competition.
I'll throw out the '00 Devils as well. Florida was a pretty easy out, though they did have 98 points that year. The Leafs had a pretty solid team overall, finishing 7th overall. The Flyers were the top team in the east that year, and then they beat the defending champion Stars. Overall, they had to go through the 3rd, 6th, 7th, and 8th overall teams.
There are a few post-'93 winners that you could make reasonable arguments for if so inclined (Colorado's two Cups were no cake walks). The pre-'93 divisional format era would have the odd candidate as well if you can get over the fact that the winner's first round opponent was usually a doormat by virtue of the "everyone in" system in place.
The '83 Islanders had to go through the 1st overall Bruins and 3rd overall dynasty-in-the-making Oilers. The Capitals and Rangers were a respectable 8th and 10th overall, pretty stiff competition by early round standards. The Oilers went through the 1st, 5th, and 4th overall teams in 1988 if you can look past sub .500 Jets. I'm not saying these are necessarily tougher roads than Pittsburgh, but it was about as tough as the format in place would reasonable produce.
I was actually curious now as to where teams would rank based on strength of opponent, so I ran the numbers. I only did '94 and onwards when the conference format was introduced. The data from before then would need some adjustments based on league size. I simply added up the overall finish of each opponent and divided by four, so the number you see listed is the average league ranking of their four opponents. They are listed in chronological order.
NYR: 10.8
NJD: 3.8
COL: 7.5
DET: 6.5
DET: 7.0
DAL: 10.3
NJD: 6.0
COL: 8.8
DET: 10.0
NJD: 10.0
TBL: 11.9
CAR: 10.5
ANA: 7.5
DET: 10.1
PIT: 6.8
OK, so based on this method (which is obviously very basic) those two Devil teams I listed above did indeed have the toughest road to the Cup. The '97 Wings are next, followed by last years Penguins. Teams finishing atop their conference are understandably handicapped by their relatively weak first and many times second round opponents. The '01 Avalanche had by far the most difficult journey for a President's Trophy winner. The '02 Red Wings had a very tough road through the west, with their number being ballooned by facing the 16th overall Hurricanes in the final. The late 90's Detroit Cup winners perhaps had more difficulty than they get credit for.
Like I mentioned above though, there are certainly other factors at play. How a team was playing when the match-up occured, the state of that team (injuries, etc) needs to be examined. There are also cases of veteran teams taking it easy in the regular season then turning it on when it counts or teams finishing high in the regular season that are not built for the playoffs. This provides a pretty good starting point though, I think.
If you're curious, the Blackhawks will score an 8.8 if they win this year, a number which is hugely inflated by facing the 18th overall Flyers (who are now in fact the lowest ranked team to ever reach a final, though they wouldn't be if you adjusted for league size). Almost unbelievably, the Flyers would only score a 10.5 if they win, simply astonishing for a #7 seed. This is a result of an unusually high number of upsets and a huge discrepency in conference strength. Bizarre to think that the Hawks finished 3rd overall yet had to beat higher quality opponents than the 18th overall team in order to reach the final. If facing a typical finals opponent (say 5th overall), the Hawks would score around 6.0 if they won.