I think McKinney will eventually start at Center, whether this year or the next.
I'm not a Ruddy fan - he had a decent year last year and is a very smart player, but he gets knocked on his butt too many times. He tends to get overpowered a lot. But, his veteran leadership is hard to pass on - unless we got a really good deal for him and the team saw that McKinney was excelling at the center position.
However, it looks like this year they are using McKinney at OG, probably b/c Nails is not fully healthy and they know that it will be difficult for him to be back at full speed.
I think our starting lineup going into camp will be:
LT - Dixon
LG - McKinney
C - Ruddy
RG - Perry
RT - Wade
I am hopeful, and I suspect the team is as well, that Nails will be able to go by the start of the season. Originally, the plan was to move Dixon back to LG and shift Nails to RG - his more natural position. But, the lack of a veteran at LT is keeping that from happening. It will be interesting, however, to see where the Dolphins slot Nails - if McKinney outplays Perry, they could put Nails on that right side next to Wade (wouldn't that be some meat on the right side!).
Of course, I would love it if Wade Smith were able to surprise and start, but the odds are against him. However, a lot of rookie OL's come in and start. Certainly Richmond Webb did and he was very good from the beginning - although he had more experience and was bigger than Smith - his extra long arms really allowed him to make up for any mistakes he might have made. So, Smith starting is a long shot. I'm not that uncomfortable with him backing up, however. And Jerman has some decent skills to be a backup at either OT spot as well.
The key to the OL, however, imo, is Nails. If he comes back healthy and the rest stay healthy, it will be a very solid group. I think Dixon will be better at LT with a year under his belt. He's probably seen everything now and there won't be any surprises out there on the corner. It will be much more instinctive for him than last year. What he did, not having played LT in a long time and not playing there much at all through the early part of training camp was pretty impressive.