Its really interesting with Intel on mobile platforms during the P4 era. Their P4 mobile chips were often terrible for temps and power use, but their Centrino/Pentium M platform was excellent despite being based on the PIII. The P4's architecture became a dead end, while the Pentium M's essentially continued to be improved, scaled up, and became the Core series.

If they had tried to force the P4 mobiles instead of rethinking and retooling the PIII core with some of the P4's FSB innovations and other things, they probably wouldn't of had as competitive mobile processors and maybe wouldn't have dethroned AMD a few years later.