The methods I outlined earlier do indeed work , with the most effective being the one you have commented on. I ought to amend the word "jump" however. The sacrum and pelvis are remarkably robust structures , easily able to accommodate my 80kgs without injury. The act of mobilising with bodyweight is not for the faint hearted, some guidance from an experienced therapist would be of value. With the foot positioned over the sacrum, repeated emphasis is provided by a downward force , mediated by alternate extension and flexion of therapists knee. The other foot is placed over the dorsum of the foot connected to the sacrum. For the less robust patient, the other two methods will work , but require levels of cooperation and strength that make them a poor second to bodyweight mobs.
If you are having a fit about these treatments , you would go into spasms watching me stretch dura. These are treatments I read about in Maitland's book years ago. Not sure which one now, but is well described by him, having been written at a time when Geoffrey Maitland was thought of as the ultimate authority on joint function and movement therapies. I see no reason to alter my affection for these safe and effective treatments, It works, patient tolerance is good with proper education and follow up. Most importantly the effect of a full restoration of Wikipedia reference-linkSIJ function cannot be ignored.