... why does a cnc have to be one size fits all? Why are cnc porters only using one specific port program on one particular head?
It doesn't, and in some cases you'll find people who will offer different programs for the same casting, or different castings w/ application-specific programs to offer some options.
But those guys are working w/ either highly specialized racing applications and raw castings intended for custom porting... or deal in a part of the performance industry where there are far more people to offer a variety of heads to (SBC & SBF).
