I don't think Sony had any say in Square developing for NGC... I think what probably happened is maybe they just didn't want to mess with multiplatform development... and they were making enough moneys and stuff on PSX... and then came PS2 and they released a number of crappy games early on, and then came the big losses from the movie, and they were just like "Ok we need to go multiplatform to stay afloat" So Sony buys some stock so not only does that give moneys to Square, but it makes it so if Square goes off and does really really good with the multiplatform stuff and the stock value shoots up, Sony makes a bunch of money...
.... right? *shrugs* k bye...
And Sony didn't really set up a win/win situation... I mean they had Square before so they were "winning", and even though NGC is getting Square, Sony is still getting their games too so it's not like they LOST Square... buuut if they do lose Square completely (which I don't see happening since they can still make lots of moneys off of PS2), the stock stuffs wouldn't really still make them be "winning"... it would be more like a consolation(sp?) prize... yep...