I can see crediting Crosby for a bit of their on-ice production together, but to stretch that all the way into claiming Crosby is responsible for their development is a reach.
Guentzel's PPG has gone up after having left Sidney Crosby and it was high in extended time away from Crosby over the past few seasons. He just got $9M AAV. At some point you just admit he's a legit good player.
Sheary had nice stats in Pittsburgh, but he also had nice stats playing with Ovechkin last season at 5v5 (61% GF and 3.36 G/60) despite playing with the corpse of Backstrom/Kuznetsov.
Sheary, like 48 point Dupuis, and 60 point Kunitz, and 25 points in 17 games with Carolina Guentzel - are simply decent players.
Perhaps you don't recall Pens fans claiming for years on here that Dupuis and Kunitz were "AHL caliber scrubs." There is a long history to the game being played here. Trashing players for Sid (including Malkin and Fleury) is a well-established pattern.
So... for full context I haven't been a part of main board convos about Crosby. That said, I don't doubt what you're saying regarding annoying fanboys -- but I'm not coming in here with any knowledge of any history of anything. And it's not my intention to trash McDavid, I think he is an amazing player.
And yet, to me, championships matter when looking back at a player's career. That is a reasonable take.
And imo part of the reason Edm hasn't won championships recently is because of lack of depth. That's also a reasonable take.
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I'm claiming that McD has done an inconsistent job at helping his teammates become better players (for every Hyman there is a Pulju), Sid has been much better in this area, and it's helped them win cups. Is Sid the ONLY factor in the development of Kunitz etc? No, of course not, that's not what I'm saying at all. Most of their development is due to lots of other factors certainly including the players themselves. But I AM saying Sid played a big part in this development, maybe 10-15% or so, which is much more than expected from a player and also important because it contributed to the Pens Stanley Cups.
To explain further, the idea is that IF the player actually becomes better (not just points, actually become better at hockey), then that player should generally do better in most situations going forward, adjusted for age. It's like if you have a good high school coach to teach you fundamentals / good habits, of course you're doing to do better in college and in life after that, you've learned the habits to help you succeed.
So the numbers you're quoting on how players like Sheary / Guentzel etc were still good after they left Crosby... I mean, to me that shows most likely they learned good habits / became better while playing with Sid, and then they actual became better players so continued to produce after leaving the nest. It has nothing to do with production on Sid's line while they were playing with Pitt.
That's how I view it especially when you consider the eye test of the players themselves and how Sid is always shown in deep discussion with his teammates on the bench and involves other players in his offense in a way that most superstars just don't do.
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TLDR -- Sid was
part of his teammates' development (not the only part), and these players' development (actual development, not just points) contributed to Pens cup wins. And also, McD hasn't done this to the same degree as a whole, and Edm hasn't won a cup yet. We'll never know for sure, but I think if McD's able to help make 1-2 low budget depth signings into a 15-25 goal scorers I think that would go a long way into helping win that one extra playoff game, that's all they need to do. And the ability to help your time win cups (in whatever manner) is something that I think matters a great deal