That is very true, and I think Luke does deserve more of a fair shot at 2B than what he has gotten so far. I also wonder what the plan is with this logjam of AAA outfield depth, especially now that they have Luke there too
I (personally) think the long term plan is that they will have Culpepper at 2B and Marek at SS if he ends up panning out has a prospect because of how good his glove is, but you are right it doesn't seem like there is an actual plan to it.