Earlier quoted context omitted.
Apple is the company that just over 10 years ago made a strategic move to remove Intel from their supply chain by purchasing a semiconductor firm and licensing ARM. Managing 'painful' transitions is a core competency of theirs.
Which acquisition are you referring to? Apple bought PA Semi in 2008 and Intrinsity in 2010.
68K -> PowerPC, practically seamless
Mac OS 9 -> BSD / OS X with excellent backward compatibility
PowerPC -> x86
x86 -> ARM
Each major transition, biting off orders of magnitude more complexity of integration. Looking at this continuum, the next logical vertical integration step for Apple is fabrication. The only question in my mind, does Tim have the guts to take that risk.