Klaus' solution is an excellent trick. I wish I had thought of it.
He is right that commenting will be very important. You will break his code if you put it back in ISA space.
In the comments I would put something like : VISA solution only, otherwise eliminate NOPs for correct jumps.
I think I would also add the 32 bit (type 8A) and NOP (type 21C) explanation.
Al Clark
www.danvillesignal.com