I guess it depends on if this person considers Michael Bennett an edge guy. I think Thomas can be an okay edge guy rushing the passer but I would much rather him inside because
A: I think he is better there
B: I value inside pressure more than edge pressure
Also McPhee doesn't really have good bend but he has been really effective in Chicago as an OLB. He isn't that Von Miller type player sure but he has been really good against the run and I think his pass rush is fairly solid. He doesn't finish sacks because he just doesn't have that bend but he gets his share of pressures at least. Like Thomas though I think McPhee is a lot more effective inside like he was with us in 2014. The Bears just don't have much depth at OLB (Sizzle and Doom in 2014) so they have not had that luxury hence why they drafted Floyd last year who can bend that edge and get them sacks. But Thomas being that SAM guy blowing up TEs in the run game and then shifting inside on passing downs is a very valuable player for just about anyone including us in the event he falls.
I guess I haven't really addressed your thoughts on whether he can be an edge guy and I think it really depends. He could adjust to the position and be really physical against the run while getting solid pass rushing numbers or he could be like Quinton Coples was on the Jets and just not fit that scheme. I think the better question though is why you wouldn't move him around as you can get so much more out of him as opposed to just leaving him on the edge. If you just stick him at OLB you are not gonna be able to maximize his potential and even if he can handle the position, you are losing out with him as he can do more. Guess we will see who gets him and how they are going to use him since as with most players, the team that takes him will go a long way to determining how his career ends up.