Hmmm…I was trying to reply to “Chronos” here…but I don’t think it will let me…
Mork’s appearance on Happy Days was NOT a backdoor pilot. It was intended as a one-off ep…but the ratings were so big that ABC was smart enough to immediately green-light a series about the Orkan alien. Mork and MIndy was a straight-up spinoff of HD.
Top of the Heap has been debated fiercely over the years…hard to believe that TV execs thought that would be a good idea for a back-door pilot… Some believe it was also simply a spin-off…
Mayberry R.F.D. is really the all-time hybrid BP/SO, isn’t it??? By all accounts, they added Ken Berry to the Andy Griffith cast with the intent of spinning them off into their own series…but it’s the same town…with many of the same characters…all in the same situation…more like an Archie Bunker’s Place or a Three’s A Crowd than a TRUE spinoff… Tomato, Tomahto…