True. If you want performance - you have to re-write the code for the new architecture otherwise it is pointless to develop the new core. The problem with deve

True. If you want performance - you have to re-write the code for the new architecture otherwise it is pointless to develop the new core. The problem with developing a good processor architecture is you have to always maintain legacy compatibility without sacrificing performance - because you know software. This adds layers of extra HW with each passing generation of the processor lying around for some legacy code.