sure they used upper bits of addresses that the hardware of the day ignored, pretty predictably the very next hardware release (68020) supported 32-bit addresse

sure they used upper bits of addresses that the hardware of the day ignored, pretty predictably the very next hardware release (68020) supported 32-bit addresses potentially breaking just about every mac binary (initially they faked it out with a PAL in the address path, they eventually faked this out in the MMU resulting in a bit of TLB thrashing) This was definitely a case of someone not planning to be successful and not looking far enough into the future