I just read the whole article on the Great Cave and the like. I actually did add Aeris back into my team via Gameshark (although she did end up sucking because her best weapon is the Princess Guard, with only 52 power, and her stats didn't increase either) and my uncle programmed it so that she actually appear when your party members "come out" of Cloud (my uncle knows how to produce Gameshark codes and taught me how, but I can't do it as well as him. Smae with Action Replay) but when you get the opportunity to talk to her, she'll only say "...", which was all my uncle could program.
However, I was surprised that she actually had dialogue until after the incident in the Crater. Although at the time I only thought it was a technical error. I also noticed the part about Sephiroth's gloves being missing, but thought it was a glitch. I'll have to see if there's more to this whole matter (I'll see if my uncle can get the Great Cave to be accessed next time he comes to visit from Sweden). Although I don't believe that Square had any plans to resurrect Aeris at all, because, as Repner said, it would destroy the whole emotional content of the story.
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