This is in relation to those who seem to experience mainly neuro like POIS symptoms. So Shaking, weakness, heaviness, tingling, spasms, restless legs, POTS.
Normally your hip / shoulders and body in general are supposed to have some ability to internally rotate this allows you to apply force into the ground and push upwards creating pressure to support the rest of your body however, In some cases due to sedentary life style & or structural bias we lose most if not all of our ability to internally rotate and thus are ability to create pressure in pelvis, torso and apply force into ground becomes compromised. Then the body compensates through whatever means necessary to hold onto just enough IR that you can continue to walk/stand and not collapse completely. One of these compensations is to increase overall muscle tension throughout the body. Here is where it relates to POIS. When you orgasm it creates a heavy muscle relaxant effect. If increased muscle tension throughout the body is a compensation then taking that away through orgasm suddenly can lead to sudden increase in physical / mental symptoms as your body suddenly freaks out over not being able to support itself properly in basic movement / positions.
As an extreme example woman when they give birth pregnancy the ligaments int eh pelvis loosen up, sometimes they get stuck in this loose state and the pelvis is no longer pressurizing supporting the guts/ diaphgram , so the pelvic floor gives way becoming hypnotic, your guts/ diaphgram lungs are literally collapsing downwards into the pelvic floor which is expanding holding only through only connective tissue strength. This loss of pressure carries through your legs down to your feet, resulting in your feet losing full stable foot contacts you shift onto the edges of your feet this creates a much less stable base to apply force, it is like you were walking on ice / wet surface all of the time now your body naturally will tighten all muscles up in a desperate attempt to stabilize and prevent from falling. Orgasm is a very powerful muscle relaxant if you take away the increased msucle tension which is desperately trying to support your body which is unable to support through normal means then it will freak out desperately trying to regain in whatever way it can.
The blind spot is that most of us here being men these issues never would cross our minds, like they would with a woman where they have pregancy, physiotherpists are specially trained to handle deal with this but men it would seem like it would never be an issue so it would go largely ignored.