Defense and forward are two vastly different things. Players on d typically take longer to get it because the position is far more nuanced. At 26 as a forward, you're generally what you are. Not that it can't happen, just that it's not the norm.
to a degree, alot has to do with the organization itself and the opportunity, or lack thereof that organization gives each player.
Could be a depth thing as we have seen in Boston in the past (perhaps not as much now but..). I haven`t a clue if Beleskey is ready for 1st or 2nd line duties but the fact remains, he plays a hard, physical game, has some decent hands and is more than willing to go to the dirty areas and I`m sorry, for as much as I have appreciated the contributions of Lucic over the years, anyone who says he still played that game with any consistency is fooling themselves, he too may regain that edge with his move but in the last few years I`ve seen a Looch who`s hit barely register or have impact, decreased goal scoring, little to no scrapping and for the salary he was going to command, I can see why the move was made
If Beleskey comes in and just plays his game, he`ll be fine