JP,
I know this question may sound a bit presumptuous but i've got to ask it: Are you sure that you haven't felt an improvement? I only ask because I too am fairly far along in my desens and, until recently, when I would orgasm or get my injections without having taken niacin first it would feel like I was back in the same-old pre-sensitization-level POIS. Even then, though, I realized that because the POIS was so stifling and because it severely impaired my cognitive function, it made sensing incremental changes in my condition very difficult. You see, when I would have an unprotected O it seemed I felt as bad as always, but when I would use niacin I could tell that my body's reaction to the orgasm was far less severe. Initially, niacin only somewhat worked for me; after using it I would feel MUCH better than I would've if I had orgasmed without taking it, but it was still only a 60-70% improvement. Further, it would still take about 3 days for me to get to a point where I'd feel comfortable engaging in public speaking, leading meetings and taking on a truly social character. Post-desensitization, however, niacin would make me feel 100% better within a few hours. Likewise, when I first began using NSAIDs to erase the symptoms of POIS I had to use 2 (200mg) Celebrex to wipe away all my symptoms. Now, I only need 50mg.
All of which is just a roundabout way of saying that although desensitization may not have improved your condition as much as you expected, it may have had a really significant (but, at times, hard to detect) impact.
I think that many people (for completely understandable reasons) go into the Desens process expecting to be cured of POIS altogether, and to be given the ability to live like a completely normal person who never worries about their orgasms. But I suspect that the truth of desens is that for most people it only reduces POIS 50-75% -- enough to make it completely manageable, but not enough to allow you to forget about it altogether. That's been my experience, at least.
