Thanks for that correction of my misreading, although I should have recalled it from my own multiuser chat system on my own quasi-OS written in MASM on a 7MHz 8088 PC circa 1984. In that system I avoided serial port interrupts and supported 24 users running at 2400bps at full speed with instantaneous echo with straight-line code pollilng all ports at maximum character throughput. Worked like a charm.
It even made money in San Diego (the FORA service) until the military (nosc) gave my competitor Usenet feeds and refused to give me the same. You’ll notice “nosc” is one of the Usenet feeds I was using in the late 80s Usenet space.policy wars after I capitulated and had to use my competitor’s system.