Massive, slow-footed right tackle. Put out on the right side so they're not facing the top pass rusher on the QB's blind side. Edge rushers are too athletic, quick, and fast. Most teams have more than one. Havenstein is a throwback to another era. One of the more head-scratching signings during McVAy's tenure. This was a Fisher pick and fit his 90's offensive philosophy.
I don't know the cap number, but I think there's not much to gain by cutting him next year so if he stays - he should have the opportunity to compete at guard or be a swing tackle. The highest paid swing tackle in the league, but we can't help that.
Next year, if Whit wants to stay - maybe move him to RT. - He can still move a bit and has good feet. Let Edwards, Notebloom, and Evans battle for the other Tackle spot.
The Rams Zone blocking scheme is not a problem, but you do need quality players with athleticism to make it work. Allen was another head scratcher - he seems to have every negative O-line trait - short, short arms, lack of power, lack of athleticism.