I think I know what this kind of error means.

When you do some modeling, things are caught up with history. Now, for some reason, not everything gets picked up (if I get this right), and may lead to some wierd results, as you say move something. Usually you get to tweak stuff in the channel box (because of history-recorded-actions), but when you get this kind of error, there may well complicate or screw up later tweaks done in the channel box.

I think there is a way to make maya register these kinds of manipulations, but I cannot remember how

I may be wrong here. Any objections?