One of most important technical details about resources in early MacOS is that it allowed the system to swap resources by using double indirect pointers (aka handles) with the lock bit stuffed into the upper 8 bits of the 32 bit. Stealing the extra flag bits from the upper bits instead of increasing the alignment to make a few lower bits available was fine on the 68000 and 68010 with their 24 Bit address space, but exploded into your face on an 020/030 with a real 32 Bit address space. It was a nightmare do develop and debug. A mix of assembler, Pascal and C without memory protection, but at least you could use ResEdit to put insults into Menu entries on school computers.