Pilling cats is not easy!! Do you have someone else helping you? It would make things so much better if you could get it down on the first try before he has time to start tasting it (easier said than done, huh).
These videos may help you with your technique: http://www.felinevideos.vet.cornell....le/index.shtml

It may seem forceful, but you've seen how stressful the alternative is, and in a lot of ways "quick and dirty" is better for all involved. Have you tried a pill gun? That will help you get it placed further back in the throat and thus make it harder for him to spit it back out.

Another idea is to maybe have the vet give him antibiotic injections. They would probably be every 4 days or so. This may or may not be a less stressful alternative.