If the 8088 had used all but one 256 8-bit values as legal instructions, all your new instructions after that point would need to start with that unused value and then you can add a maximum of 256 instructions by using the next byte. End result is 511 instructions can be encoded in 16-bits.
I want this so bad. Please please please.
No,no! I mustn’t hope. Hope is the bringer of disappointment.