>>koyote+ve
It was a different era, one in which computers were a lot slower, source control was a lot more primitive, a lot of basic stuff was still being invented, but … yeah, I feel a lot better about my own productivity now!
>>rauhl+Af
While I agree about productivity now (although rewriting a source for cat that is used decades later seems very productive), I think the above commenter has it correct that it was probably a side project that he worked on and released after 6 months and not so much the speed of the CPUs.