Why not? Watson has only been playing Football for a couple years and is one of the most athletic Tackle prospects ever. He's not fast, but I'd bet he'd have great hands (he's a former backetball player with giant hands) and would be an amazing blocker for a TE. Usually when a player converts its from TE to T (like Joe Staley) but this may be a great way to get the best player on the field for the 49ers. They could draft him as a project player and use him in "big" packages as a fullback or extra TE but also keep him as the swing Tackle. By all accounts he's a football savant and has picked up more in two years than some players do in a lifetime, I think this guy could be a great value pickup for a team that has everything.