Very hot tantra experience last night. A liquid lightning bolt reached up through my spine up to the heart level as I approached orgasm. Rising like a thermometer, it was unmistakably the same energy I felt during my initial kundalini surge - just much slower and manageable and this time not reaching the crown. It was accompanied by vigorous involuntary spinal shaking (like a dog shaking off its wet coat). It was truly awesome. I might dare to say it felt better than an ejaculatory orgasm, without actually being an orgasm.
This from practicing AYP plus solo tantra with holdback and blocking over the long term. Holdback meaning pause and wait while fully excited, then continue. Blocking method used on most but not all orgasms. Very rarely do I ever withhold orgasm, maybe once every couple months (the exception is when it feels like it's the natural, right thing to do - otherwise it is painful). And I just do solo practice whenever I feel like it (every 1-3 days for me), not trying to enforce any form of celibacy on myself. Looking forward to more liquid light filling the sushumna as this process continues.