'all knights become bishops, all bishops become queens'
Ah. I was thinking you meant something like all N become Fibnif, all B
become FA, all Q become RN and so on.
As far as tending to immobility goes, that's one way to make a game of
limited length. Too bad that contest is finished!
So, work out the details of your idea, give it a try or two, and then mail
it to [email protected]; okay?