Agreed. Plus all versatility talk is about the ability in dire circumstances to have a player moved to a "new" position. The OL is a different dynamic in that regard than say a Y-receiver moving to the slot, or a CB moving to safety. If Collins were to be out for an extended period, then you may very see Williams/McGovern getting a lot more consideration. Additionally, I'm sure there's some ego involved ... for example, say it maybe coach Philbin convinced this team to sign Erving and now he needs to prove he made the right call ...