I've been reading some of the older TOS novels, and note that this pair, who had done the 2 Phoenix novels (which I found utterly incomprehensible when I read them as an adolescent) also wrote a Pocket book, Triangle. I'm sure this has been asked before, but whatever happened to them? Seemed like they were mantle-holders for a while and then pfft.
Actually they wrote two novels for Pocket Triangle
and The Prometheus Design
Not sure what they're doing now, but as long as the stay away from writing Star Trek novels I'm happy.