I meant that if Subban could really piece his game together and emulate a bit of what his brother has, he could be an all-star defenceman with his offensive powerplay ability tied in with great determination and speed.
Tryamkin, for sure, is the safer bet because he's big and he can skate. Will he ever be a powerplay guy? don't think so. And I don't see his game taking him anywhere near being considered an offensive guy.
Will Subban ever be an-all star? Doubtful, but if he managed to piece his game together and find his comfort zone, improve his defensive game he could be something.
For the record, I take Tryamkin 9 times out of 10.
You're equating upside with all-star ability and all-star ability with offensive ability, which I think is the wrong way to look at it.
The chances of Subban magically finding a solid defensive game are not much better than the chances of Tryamkin pulling an offensive game out of thin air.
In the end, if Subban's ultimate upside is that of a one-dimensional powerplay specialist/offensive wizard who will never be viable on the penalty kill or in matchup situations, and Tryamkin's ultimate upside is that of a wrangley, high minute munching shutdown defenseman who will never be viable on the powerplay, there's not much of an argument to be made that Subban's upside is any higher, IMO.
Furthermore, hoping that Subban "emulates a little bit of what his brother has" and therefore becoming an all-star defenseman is no more valid, reasonable, or possible than hoping that Tryamkin "emulates a little bit of what Chara has" and therefore becomes the all-star-equivalent stud high-minute munching shutdown defenseman.
Both have fundamental limitations that basically prevent either of them from becoming a complete two-way #1 defenseman, even if everything goes perfectly for them. Both have pretty similar high-end peak, everything-magically-goes-right upside, but Tryamkin is more of a sure bet to be a useful/serviceable piece (and therefore also has a higher opportunity and possibility of hitting that maximum peak).