Havenstein is one inch taller that Whitworth, so I don't think his size is an issue.
My two cents worth.
Pretty soon we will lose Sullivan and Whitworth. Allen may end up at center in two years or less, I think Demby will end up taking over for Brown next year. I also feel that Noteboom will end up taking over for Whitworth when he retires. Honestly we can't afford to lose Saffold too, as we have to maintain some sense of continuity on the Oline. Also I'm pretty sure Havenstein will be staying. We are going to have a lot of changes on the Oline, and we can't just let people walk when they will be seriously needed. Saffold in my estimation, along with Havenstein are the only ones now playing who will in all likely hood be the ones remaining. I could be wrong, but the Oline is not an area where we are relying on a bunch of newbies, that would be a disaster in the making. Again only my two cents worth.