The other point to make about Ron Francis (and then I'll stop talking about him) is I don't think he's as good as his numbers suggest (which is a strange thing to say about a player who was very good defensively, and who developed into a well-respected leader).
From 1982 to 1991 (covering ages 18 to 27), Francis was never in the top ten in scoring in any season. Nor was he in the top ten in scoring overall (that's also true if you exclude his rookie season, or even if you cherry-pick his few best years in that range).
I think there were some challenges in getting him integrated with the Pens' killer offense (65 points in his first 84 games in Pittsburgh). But once he started getting top icetime, his stats shot upwards. He was a top ten scorer four times in a row (three of those in the top five) from ages 31 to 34. It's not impossible that Francis got better with age, but it's much more likely that his stats got a big boost by getting so much ice time with Lemieux, Jagr and Robitaille.
Corroborating that notion is, as soon as Francis left Pittsburgh, his offense plummeted (he scored 25 fewer points in 1999 - dropping from tied for 5th to tied for 69th in scoring - despite playing basically the same number of games in both years). That same year, Jagr had his best offensive season - I don't doubt that playing with Francis helped Jagr, but it seems clear who needed who more.
The only other time in Francis's career when he placed in the top ten in scoring was in 2002, when he was tied for 9th. That's routinely regarded as one the weaker years for top-end talent (for example, Forsberg missed the entire regular season; Lemieux missed two-thirds; Lindros, Bure, Thornton and Kovalev all missed enough to keep them out of the top ten).
I actually like and respect Ron Francis a lot as a player. As I mentioned in one of my previous posts, he's pretty much the perfect complementary player for a championship team. But even though he's the 5th highest scoring player in NHL history, he's not anywhere close to a top five (or probably even a top fifty) scoring talent - his numbers are what they are thanks to a perfect storm of playing in a high-scoring era and having his numbers boosted by playing on a run-and-gun team after his offensive peak "should" have ended.
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The other player who we might want to consider making a "preemptive" argument against - Scott Niedermayer. There seem to be a number of people in the mainstream hockey media who talk about him as if he's a top ten defenseman all-time.
