It was more trouble that it was worth. If one needs such a setup, it's about the same work doing it manually as using the local/ppi system - many extensions need manual work in both cases.
It was also rarely used, in fact most mentions were by people new to TC, who shouldn't have had to dive that deep at first tries. If you search, you'll find many who copied the bootcode from a third party site, and then ask why some things broke.