So, now I can tell you this story...
...Last year I came to Morgana's Chamber in NYC to buy a new deck. I couldn't decide whether to buy the Visconti gold or not. I hemmed and hawed. The young woman behind the counter pulled out a deck and quickly went all through it looking for the aces and putting the cards in piles. Then she told me my answer was "no" and the reason came up as being about money, actually. How right she was !
Hahahah. Now I know, Moonsinger, she did a yes/no reading for me with exactly the method you described.
There is something I don't understand in your description, however, you say, the other aces give some insight into the reason. But how? I mean, if you turn over all four aces, you will always have the same cards -- duh, the four aces ... how can they give insight? Do you mean, the cards surounding the other aces?
The other thing is, it will be yes if upright, and no if reversed, right? So then of course, one would have to make sure the cards have been prepped for reversals, otherwise...