Tufte? If so, it takes longer for power forward-esque players to develop because it can take multiple years to eventually grow into your body and become comfortable with it. Plus, add in the fact that on top of that, he was always drafted as a long-term project. Granted none of Avs drafted players have turned into anything amazing, but every team tends to lose one or two lads which becomes something since their drafted team gives up on them and needs an extra year or two to figure out/adjust their role (happens to every team in the NHL though).
On top of that, there is definitely some "I have to perform" fire lit under players' arses when they get traded or move to another club. When you get drafted, especially as a first rounder there tends to be a comfortable side that enters you knowing that you are a property of a team for at least the next three to five years and maybe even longer. When a team gets rid of you, it could awaken that internal drive that got him drafted in the first place, knowing that you can't take advantage of the situation anymore. That's exactly what happened to Nuke IMHO, he thought he could take advantage of being part of an NHL team and it made him soft inside. When Sakic signed him, he knew this was his last chance to make it or break it in the NHL and that pressure told him he had to take it seriously to the point he works out after almost every game. With all that written, we ain't expecting Tufte to turn into a 20-goal scorer, we all have projected on the bottom two lines and for a reason.