If you know you're going to have to experiment a lot on some aspect of the game/product, it seems to make sense to isolate that part, removing the commonalities into some kind of framework (perhaps informal, jury-rigged, so you can iterate on just that aspect.

A bit like the Wright brothers building a wind tunnel, so they could experiment quickly with control systems.

But Id wrote some great games, so maybe I'm missing how they handled this aspect...