[tom_]

I don't know how the 6502's PC increment actually worked, but it was an exception to the general rule of page crossings (or the possibility thereof) incurring a penalty, or, as was also sometimes the case, just ignored entirely. (One big advantage of the latter approach: doing nothing does take 0 cycles.)

The full 16 bits would be incremented after each instruction byte fetched, and it didn't cost any extra if there was a carry out of the MSB.