[petek]

I would think the chemistry of the batteries would normalize after a very short period of time so that you could have the two batteries wired in parallel without a problem.

One battery "topping off" the other would only occur for a short period of time (until the voltages equalized).

If one of the batteries was dead, then you'd have a problem. But if both batteries were in good condition, I don't think there would be a problem.