Whether maithuna was, or is, practised literally is a genuine and long-running disagreement among both practitioners and scholars of Tantra rather than a settled question with one accepted answer, and the disagreement runs along the same line that divides Vamachara, the left-hand path willing to use the pancamakara literally under ritual conditions, from Dakshinachara, the right-hand path that has generally read the five Ms symbolically from the outset, treating maithuna as an inner union of currents within the subtle body rather than a physical act involving another person.
Textual scholars of Tantra note that many of the surviving Kaula and Vajrayana sources most associated with literal maithuna are themselves ambiguous or deliberately encoded, using what scholars call twilight language, sandhya bhasha, in which sexual and physiological vocabulary is understood by initiated readers to refer to internal yogic processes, breath, subtle channels and the movement of consciousness, rather than to the literal acts the words describe on their surface, which means even specialists disagree case by case about which passages in which texts intend a literal reading and which do not. This ritual practice, whichever way particular lineages have read it, sits within a Tantric literature overwhelmingly occupied with mantra, visualisation, deity yoga and subtle-body practice that has nothing to do with sexuality at all, so that maithuna's prominence in popular Western awareness of Tantra considerably overstates its place within the tradition's own much larger and mostly non-sexual body of practice, a disproportion Tantric scholars have repeatedly pointed out as a distortion introduced by outside popularisation rather than a reflection of the textual corpus itself.