>>TP knit circles around anything else I had on CP/M.
>
>My first machine was a used Apple //e with a Z80 card and a RAM card (with a WHOLE 1meg of RAM). I would boot to RAMDisk C:, load TP AND my working files to C: and I was cooking along at machine speed. Ran a (dog) pedigree program that I had written for quite a while. Then came assembler class and my instructor couldn't read the 8080 code. C'mon, there's not THAT much difference between JUM and JMP.

Z80 had too many registers and knew how to combine them into 16-bit registers, plus those darn index registers. Above what can be understood from the 650x perspective.