Unfortunately there were also badly written, overwriting viruses that destroyed the host.
I made a COM-to-EXE convertor back in time so that I can compress them with LZEXE (I don't remember anything about it, but I guess I just prepended an empty relocation table). It would have been interesting to incorporate that functionality in a virus.
its size was right at the edge of segment (64k) so when a virus appended to the .com binary, volkov stopped working