Thomas Huebl perhaps wrote about Tibetan buddhist tantra. Hindu tantra (not what is sold by charlatans) is for aversion (not intimacy) to sex (and other four things) in quest of spiritual advancement.
Yes, Hindu culture treats sex like the West treats death, it is quite strange.
You cannot advance "spiritually" by cutting off your life energy, but by condemning the sex energy, this is exactly what you do.
I place "spirituality" in quotes because it isn't really the thing.
Integrating the whole is the purpose of religion.
That whole cannot exclude anything.
I suppose this is why, though, that Hindu sanyas is traditionally taken late in life, except by that time the body is almost impotent, how can energies grow now?
That is one of the most promising things about the current atmosphere, young people are beginning to enter sanyas and so there are more enlightened beings today perhaps than any time in history - certainly there are more working towards it.
Sanyas is renunciation, but today what is renounced is the ego alone, to claim the activities of life is the problem, life happens as it will - there is no individual doer.
This is proving to be a very successful approach.
Of course, it is is also why the traditionalists despised Osho.
You know what is unique about the many thousands of his sanyasins I have encountered? None are fanatical, all are loving from a very young age. You cannot imagine an Osho sanyasin fighting with Muslims and causing a riot, he loves the Muslim too because they have given the world Sufis.
The problem with the traditions is it feeds the ego for so long that even if you intend to take sanyas seriously later in life, there are so many hard-grained beliefs to move past it is almost impossible and time is so much shorter now.
Far better to drop them earlier, although better still is to never pick them up.