First things first, Harris has the athleticism to play in this system.  He's very good at making blocks on the second level and in combo blocks at the line.  He's noted for his intellect, both on the field and off, and should have little trouble digesting Denver's blocking schemes.  His lateral agility is first round material as he can mirror speed rushers.  He has a very quick hand punch, and PFW scouts believe he has more pop than you'd expect for his size.  Despite only average height for a tackle, he still can run pass rushers wide of the pocket with his arm extension, hand speed, and foot quickness.  Very good technique in pass pro.

The problem for me is that Harris seems to lack that killer instinct.  He was hot and cold at the Senior Bowl, ultimately lowering his stock out of round one, and he didn't always take advantage of his athleticism.  With his agility, he should hold up better on an island, but he took too many false steps and overcorrected in the Senior Bowl.  However, Harris was a much better pass protector during the season ,and that is his strength.  Will struggle with the bull rush, as Harris occasionally sets too high, and though he bends at the knees, he lacks the base to hold up consistently.    Harris might be too smart for his own good.  He doesn't always play with a killer instinct, and could take time to get the cut blocking aspect down.  Can he be a ruthless player unafraid to chop down defenders?

Still, as a third rounder he's great value, and there's still a lot to like.  He has an outstanding pedigree and plenty of experience.  I also like that Denver is still focusing on athleticism first and foremost in their linemen.  Obviously, I can't converse with these players, or see the same reports as the coaches, so if they feel he has the nastiness to play in Denver's zone system, I'm all for it, because he's an outstanding athlete and potential long term starter on the left side.  I'm not so sure he can bulk up much more, his frame is only average, and too much bulk would be counterintuitive.  

Harris has obvious potential, but does he have the drive and tenacity to be great?  If he was a little tougher, he could be a Khalif Barnes type steal, more than likely, I see him as an Adrian Jones or Mike Gandy wave type player, though there's always the chance he could have a career like the other Gandy, Wayne.