In the mean time, until I can find time to digest what has been posted with respect to methodology, it might be reasonable to run this experiment.
Rather than removing an ace, I think the equivalent adjustment for my software would be to discard and count an ace at the start of each shoe (after the burn card). This would place all instances of A,A vs ? into a context where at least three aces have been observed and counted just they would be when playing A,A after splitting.
Does this sound reasonable?
Bookmarks