Spoken like a true fan
First of all, even if everyone on this message board stopped watching it in syndication, would that really do anything? It could just make Carsey-Werner stop showing it completely. How many board members are there? Even if there was 1,000 (which I'm sure there isn't), I would guess that only 600 of them would actually participate. Obviously there is a great number of viewers who tune in to Roseanne on Nick@Nite, much more than 600.
Second of all, could we actually last for a long time without watching the show? Unless we all have tapes of the show, I don't think we would be able to do it. I fall asleep with Ncik@Nite on every night. So even though I'm sleeping, my TV is still watching Nick@Nite, including Roseanne.
Once we get to 16 pages of members agreeing to it, I will of course participate. Its a good idea, but I am not sure if it will work.