There's nothing easy about adding 20lbs and still being effective as a DE in ANY scheme. In a 3-4 though, a DE has to play the run first and he has to be at the very least 295lbs to be effective..preferably 300+. Pass rushing success for a 3-4 DE, is determined more by how well you can shed your blockers, AFTER you penetrate the LOS (if you even can). Of course, this is just my opinion when taking on 2 blockers going between the gaps. Naturally, there are stunts designed to help DE's and confuse OL and that is part of it too. The first question for 3-4 DE should always be, How good is he against the run? For example, how many forced fumbles or fumble recoveries did he have in his college career? How many tackles were on running plays and how many on were on passing plays etc? This where film study is crucial on a DE prospect. Scouts could say, "he looks good on passing plays, but can't shed well or gets sealed off against the run too many times"...for example.