I have been following the AYP path for a little over 5 years – I do deep meditation and spinal breathing. I have periodically had to scale back on the SB (either by dropping it for a period of time or cutting back on the number of rounds). I have mediated every day during this 5 year period. The overload issues have been pretty minor – I get slightly irritable or my jaw clenches up during meditation.
What makes AYP tricky, I think, is that Yogani has laid out this series of powerful practices and it’s easy to let your desire to move forward get the best of your judgment. As he noted somewhere on this site, in the old days these practices were most likely handed out very sparingly. This is why he rightly puts an enormous amount of emphasis on self-pacing.
When I first encountered AYP, I thought, well, I will add practice X and in a month or two I will add practice Y, etc. I hit a wall pretty fast. What also makes it complicated is that there must be tremendous variation in how much practice is too much. Currently I do 2/3 rounds of SB and then meditate. This places me right on the edge of overload. This alone has been sufficient, in my case, to activate kundalini – sensations of heat and coolness radiating through my back, hot sensations along my spine, strange sensations in my forehead, etc.
I had a partial kundalini awakening in the 70s, which might partly account for why I am so sensitive to the practices- but I don’t know that. He states that every one of us has a “unique matrix of obstructions”, which is no doubt also true and would account for the variation in what people can handle. It truly is an “experienced based” practice, since you have to adjust your practices based on your experiences rather than work with some arbitrary timetable in mind.