Disclaimer: Not a hardware engineer, nor a CP/M aficionado (though I definitely remember Gary Kildall), but a former AST Research (later AST Computer) employee. AST was an "expansion board" manufacturer turned systems OEM. During the transition from memory and connectivity boards to desktops, the company's top hardware engineers explored an architecture they based on an "intelligent, arbitrated, multi-master bus." The notion was to speed up operations and increase power by designing a bus that accommodated multiple processors (on boards, of course) operating independently - arbitrated by a central CPU. It never flew - but I always thought it an elegant model. This was in the 1986 timeframe, long before GPU's became popular.
Funnily enough, I just saw an old Computer Chronicles episode the other day which talked about how slow the bus was and they had Dell showing off a 486 + graphics board blowing away the same 486 and an ISA? graphics card.
If you haven’t seen it already, the 8 Bit Guy has a fun video about working in AST’s tech support in the 90’s:
