To me the most important nugget in Peter King's otherwise boring piece was this:
"Everyone said all the right things about Ugoh, but the fact is this is a stunning demotion. Johnson's a hold-the-fort guy, and I'm told the decision was made because Ugoh might play 50 snaps a game fine and get beat on five others, or lose focus or make an assignment error. That's four too many for a team that can't afford to get Manning hurt."
More and more, I think the move of Ugoh to RT is a permanent change. The Colts likely agree with most of us, that Ugoh is more talented that CJ. BUT when you feel that your LT takes 5-6 plays off a game you can't afford to put that on your QB's blindside. At least when Ugoh takes a play off at RT Peyton should see it coming. CJ may not be as good, but Colt's probably know what they've got, and they can scheme for his overall level of strength/weakness. Whereas with Ugoh you never know when he might take the play off, so do you constantly scheme to that with assistance from TE's and RB's? Which you may not need on 90% of the plays?
I also think the Colt's know that Diem is near the end of his career, and he will likely not make it through the whole season healthy. They think Ugoh is talented enough to excel at Tackle in the NFL but is a liability 4-6 plays a game and figure they are better off moving that liability from the blindside to the right side. I'm convinced more than ever this is NOT a Ploy, and short of CJ getting hurt Ugoh will stay at RT or as the backup. What will be really telling is if CJ would get hurt, do they move Ugoh or bring in one of the other subs to play LT and leave Ugoh at RT? That move would clearly end all speculation in my opinion.
The bigger question then is why if the Colts "knew" this already why didn't they address it in the Draft? I'm no draft Junkie but were there no decent LT options on the board better than Charlie Johnon when the Colts drafted in Rounds 1 and 2 maybe even 3?