Me: "I've got a bad feeling about this..."
Friend: "Why?"
Me: "Autosave just kicked off for no apparent reason... best check for traps."
Yes, this exactly. One or twice, not the whole game. it gives the player a chance to sit down and say, "hm, what else is common between these situations?"
You could also simply not have the game give feedback to the player when it does saves like this, perhaps even calling them something other than auto saves. It's really not hard to find a solution to this problem at all. Hell, if you are concerned about corrupted files if the player closed it without a prompt you could just store them in a new directory for safety, worse comes to worse they end up without a safety save they otherwise wouldn't have had anyways.
