I just went and watched all five of Dallas Thomas' game cut ups on YouTube. Hadn't watched anything before that. Barely knew who he was.
I like him. He doesn't flash, but he's very solid and I think will make a very solid NFL lineman. He's very smooth and very aware. I really like his awareness on stunts and games up front, though Florida is so active it got to him at times. He can combo block and then reach a defender very well, which stems from his above average solid footwork. Maintains proper knee bend and technique.
The negatives, such as they are, are just a lack of anything outstanding. The only truly exceptional aspect of his game are his run blocking angles. His are pretty much perfect, especially on second level blocks. The running back slides in right behind him and there's nothing for the defender to do. As an athlete I think he's okay. He's not a plodder; his feet are quick and active, especially his first few steps. But he's hardly Pouncey or Jonathan Cooper, leading a running back 20 yards downfield. His power is somewhat inconsistent. If he doesn't time his block well, he doesn't have the huge natural power to overwhelm someone and can get stoned or just sort of bounce off or get shed.
The main question seems to be: can he play left tackle in the NFL? I honestly don't know. Having relatively short arms will hurt him. One of the cutups on YouTube is his game against Alabama in 2011 where he played left tackle the entire game, often lining up against future 2nd round pick Courtney Upshaw. I think he does quite well, actually. But Upshaw is the kind of solid, powerful DE Thomas would do well against. He's no threat at all on an outside rush. Apparently he did very well against JaDaveon Clowney at LT in 2011, as well, but as that video isn't on YouTube I can't verify that claim. Clowney's stat line in 2011 does show him only making one tackle and one assist and no sacks against Tennessee.
Clowney did only have eight sacks that year, however. He had 13 this year.