I was figuring out how early digital analog synths (i.e. with digital oscillators) were working, I always wondered why they only had saw, pulse, and a combination of those, but not some other waveforms (triangle, sine). I thought that is related to the richer harmonic content the two gives, but it turned out in my experiments that a combined pulse/saw generator can be implemented as simple as add hl,de, so that's likely the reason. It naturally gives the saw waveform in the MSB, and putting a threshold on it (with cp N) gives pulse with duty cycle control. We're using the latter quite often, but maybe there is some use to the saw itself too?
I tried a naive approach, use top 4 bits to generate a short pulse of different width every loop, sounds bad and not usable.