Hi Mystiq:
While I am sure some would disagree, I don't think orgasm itself has much to do with yoga. It is related to reproduction -- the ecstatic engine that drives reproduction. And, as we know, it involves body, heart and mind, and all of that is related to the rearing of the family too. That is a crossover of orgasm into the spiritual arena. Whenever we care for others more than ourselves, something spiritual is going on. It can come through the reproductive cycle like that. This is what makes the family sacred.
Beyond that, sex gets truly yogic when we begin to work pre-orgasmincally with it in extended cultivation. This also has a relationship to lengthening and deepening orgasm itself, but if we are aiming for that we are not doing yoga really. So much of modern tantra is like that:
"Come to our tantra class. Learn how to have longer deeper orgasms."
Perhaps those who are born with such tendencies have taken a lot of tantra classes in a past life.
But it (yoga) is not about the orgasm.
If systematic cultivation is done pre-orgasmically, in addition to having an integrated routine of sitting practices (done separately), then something different will be happening. The ecstatic component of that will no longer be for reproduction and will go up toward human spiritual transformation. It is a different thing entirely, though using the same energy that reproduction does. Success depends on the presence of inner silence, and steady commitment and persistence over time.
Siddhasana, mudras, bandhas and pranayama accomplish the same objectives as tantric sex -- cultivation of the ecstatic conductivity (shakti) component of the shakti/shiva duo. Inner silence cultivated in deep meditation and samyama is the shiva component. These means can be used by celibates and by non-celibate tantrics.
If it is an analysis of orgasm we are doing here, that is about as far as we go with it and still be talking about yoga. The rest (the quest for the perfect orgasm) is something else and can be a distraction to yoga, and to everything else we are doing in our life. Maybe that is why many cultures try and put a lid on sex. It doesn't work, of course. It leads to repressed societies and aberrant behavior, or worse.
Sex is what it is. We are all inclined to be obsessed with sex either for or against. It cannot be ignored. I think one of the real strengths of tantra is that is enables serious practitioners to redirect the natural obsession with sex toward spiritual transformation. That is bhakti! Those who really know the methods of tantra, have no fear about sex and less obsession, because the lion's share of it goes toward expansion of ecstatic conductivity within them. It is like a never-ending orgasm, but not really. If it does not end, it is not orgasm anymore. It is a different thing -- a component of enlightenment, life in ecstatic bliss. Then "the act" is about the higher mudras like sambhavi and kechari, and the filling up of the heart to become a channel of endless divine love pouring out into the world. That is the best "orgasm" of all.
The guru is in you.