If a 5th round pick mostly end up as depth players and special teams player which is what Thompson is right now. He still has to develop his route running and catching but I doubt you will find any NFL ready TE in the 5th unless he has serious character issues. Thompson's size/athleticism is nothing special at DE while it has a chance to be elite at TE. In the 5th-7th round all teams are looking for are depth players with the high upside and Thompson fits that bill no matter where he played at college. Players switching positions when they get into the NFL is a rare and unheard of thing. More then a few QB's have done it and had respectable careers; Antwaan Randle El and Brain Mitchell come to mind. Antonio Gates and Jimmy Graham played basketball for the majority of their college careers(although Graham did play one season at TE where he caught an astounding 19 passes) and I doubt transitioning from the basketball court is easier then switching from a defensive end.