And the effort could not be avoided - you can only trade present effort for future effort, that is more work put upfront into CPU design vs more work later on to convince developers to recompile the apps. The problem with the former is that you make all the effort and still don't get the flexibility, whereas in the latter case the extra flexibility can can in handy in more ways that one, and some of which we cannot foresee today.

Code for flexibility, I say.