I often get questioned as to whether I have now put out all the Xing Yi material worth printing or whether there's more. Are you kidding? There's a hell of a lot more. But I de-emphasize it, and constantly state that I've pretty much laid out everything you need to get cranking, because the additional super cool stuff has the following unattractive properties:
(i) Whenever I put a toe forward with a really advanced point, somebody somewhere will always kick up a fuss about it, suggesting it's not useful or not their way or dangerous or some other blowback and I'm just sick of dealing with it. Basically all noise along the lines of he can't be a man cause he doesn't smoke the same cigarettes as me, but I'm tired of it.
(ii) You need to have ignited and must be able to instant-ON the ARC flow to get anything of advanced Xing Yi work.
(iii) A lot of the really cool advanced stuff sounds and look like nothing to see here, when written or filmed. Must be experienced but that's just too much work for most of us, I do understand.
Thus has it been wisely written, of ancient times: SILENCE IS GOLDEN （沈默是金）
I'll give you a very small example, and by checking your own reactions against the 3 points above you'll instantly grok for yourself exactly why I don't bother.
For example: I recently wrote about (mental) extension of index finger in the Xing Yi balanced (50-50) standing meditation. It's a straightforward and authentic teaching that really does a job on you. But it's also the precursor to advanced work with the Snake animal (one of the 12, covered in book Radical Xingyi Energetics and also in Vimeo movie Transformative Animals). Once you can mentally initiate, control, and intensify the flow out through the index finger of each hand, next step is, you incorporate that into Snake technique. It does not show in the outer performance of Snake (hidden teaching point of which there are many). Internally you are connecting the hip/dantian energy activation on each rep with immediate outflow through both index fingers on each of the 3 sub-moves of each Snake strike rep. (If you have no idea WTH I'm talking about here please move on you have landed in the wrong blog by mistake).
Remember if you work with this that your two fingers (and overall hands and arms too for that matter) must as always be worked loose and light - mentally engaged and energetically extended but without physical and muscular tension. That is the foundational paradox of all this work. Also, BEGIN the rep (start of 1st sub-move) with your mind and energy engaging the dantian and hips. This is absolutely essential, you cannot begin with the fingers. THEN quickly project it, fuse it really, with the lightly extended fingers. But don't lose the hip/dantian connection as you go.
In essence, your two index fingers (FULLY ENERGIZED via the ARC etc as I've already covered everywhere) are functioning as the two 'fangs' of the snake. Sure it sounds super hokey, but that's not the point, the point is it's a genuine and incredibly interesting training effect, just a totally gonzo experience when you really connect the lower trunk with the two 'fangs' as you move. It completely transforms your understanding and performance and harvest of Snake technique, but most importantly yields a huge energy intensification harvest per-rep. GONZO and mindblowing.
In terms of deployment, this snake fang energy is the training basis for the quick finger push (fire mode in Juice book) that I always demo in my Tai Chi seminars (fire mode is really borrowed over from Xing Yi).
OK so now I've outed an 'advanced' Xingyi teaching, just above. It's based on all the prior foundation work (so tedious!), it sounds ridiculously simple and trivial (How can that be anything?) and probably seems to you dangerous, stupid, contrary to your own beloved teacher's doctrines, or some other dumbass external objection has doubtless arisen in your mind.
So you see why I hardly bother with this kind of thing, but there's tons more of it.