Quotations from:

Aghora - At The Left Hand Of God

Robert E. Svoboda

"The merely curious have no business dabbling in Tantra, but some so-called gurus in the West encourage their half-baked followers to do so. Such self-delusive activity reinforces the crystallizations of the personality which prevent spiritual progress. Tantric rituals are sacrificial rites. Though herbs, minerals, and animals are used as offerings, they are secondary to the true offering, the sacrifice of one's limited self into the sacrificial fires of penance. In the Panchamakara ritual the female is the fire into which the male offers semen, just as clarified butter is offered in orthodox fire worship.

Ordinary sex is no sacrifice. When two people come together to copulate they usually seek gratification for themselves, the slaking of their lust. Perhaps indirectly they will try to satisfy their partners. Tantric sex becomes possible only when one has totally effaced one's own personality and offers oneself for the gratification of the deity, the universe incarnate.

This is one reason Tantra has always been a closely guarded secret. The danger of abusable knowledge falling into the hands of the unworthy has limited its spread. One should never seek to practice classical Tantra without a guru because no Tantric texts exist which provide thoroughly accurate details of any ritual. Each text omits an essential step, or includes false information, and only through a guru can the reality, handed down from teacher to disciple over generations, be known.
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Unfortunately, even the Tantric attitude can be dangerous. As one accumulates power, the ego will balloon out unless the personality is continuously incinerated simultaneously. Hence Tantra's insistence that power be objectified and personified. Since Tantric ritual can be used to create emotions which did not previously exist, perhaps adoption of the Tantric attitude can prove therapeutic for those many today who suffer from emotional paralysis. Hence Vimalananda's insistence on the greatness of motherly love.
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Vimalananda was an extremist. He was certain that anything worth doing was worth doing well, and he was ready to stake his all to ensure that whatever he began was completed. For him, Aghora was the doctrine of no return, a personal creed which demanded relinquishing all in exchange for divine love. He wanted to warn spiritual dilettantes in the West that the frivolity with which they treat discipline and the self-delusion they attempt to pass off as enlightenment is merely a cheating of their own consciousness which leads only to the pit. For example, when I was once unwise enough to comment that a certain guru was supposedly awakening his disciples' Kundalinis by boffing them with a peacock feather duster, Vimalananda exploded in reply: "Has the Kundalini Shakti become so cheap that some so-called godman can awaken it in multitudes of people all at once? Oh, no! Were our Rishis (ancient seers) fools to spend decades out in the jungles working at hard penances to awaken Kundalini and to perfect Aghora? No, the people who think they can buy Kundalini are the fools. Westerners think they can purchase knowledge, but all they get for their money is fake teachers from India who dish out any slop to them and get rich on their gullibility."

Robert E. Svoboda; Aghora - at the left hand of God
Rupa & Co, New Delhi, 1986