Billy takes the weight

Well my weight anyway !
A long day with horses today. Starting with helping a friend loading a horse to go to vet hospital for some scans. I only went there to deliver a very late Christmas present ( Imprinting the New Born Foal).
Returning to the yard I started with Billy as dinner time was fast approaching. Do NOT play with Filly over dinner, if she can't get oats then bits of Tim will do just as well !
The aim today was to get Billy happy at taking my full weight. Putting the plan to use again we quickly got to the stage of Billy being ready for me to lie on. The pattern was very similar to the last session. He was willing to stand next to me on the mounting block and happy to have me lean over him, but when I added weight he attempted to escape by moving of rapidly. I would like to distinguish "drift" from "escape". Drift is a mostly left brain wandering off as I mount, not desirable but rideable even when lying on my stomach. "Escape" is a more right brain, unconfident rapid movement away from pressure and I tend to roll off. So far I have mostly landed on my feet. During an escape I rapidly manoeuvre him back to the mounting block so that the psychological pressure of me being on his back is not removed until he is back in position next to me on the block when reward and rest is given. If I did not do this he would learn that comfort could be obtained by getting me off his back.
Out of 5 attempts to lie on Billy with all my weight 3 were totally successful with him not moving at all. These were the last 3 so progress was made. In fact he looked very confident towards the end.
I also did lots of work on his basic porcupine yields. He is very good with fore quarter yields but hind quarter are more problematic. They need to improve before we ride him as I want to be able to do a hind quarter yield when on him so that I can easily disengage his hind quarters if he moves off a bit too fast.
After dinner I turned to Filly. I wanted to run through the plan all the way to mounting her, and it went very well. The touch all over has improved dramatically. She is much calmer as I touch her flank and teat area. Not an Angel yet, but the Devil is in retreat. Very soon I was sat on her again and she seemed very confident. She loves the neck flexion I ask for as soon as I mount. This involves putting pressure on the lead rope to get her to turn her head towards me. Of course this gives her the perfect opportunity to bite my leg. To thwart her I but my foot up along her neck ( a trick I learnt from a video of Pat Parelli ). In this position she cannot flex enough to get at my leg and soon gives up. "Foiled again, but fun trying" I can almost see her think. The only habit I need to break now is the couple of steps she takes as I mount.
In preparation for her to "follow the rail" I also did lots of circling. I am trying to get to 5 circles at the same gait with no input from me at all. This teaches her the horses responsibilities "Maintain gait, maintain direction, look where you are going". I send her on the circle and then relax and become neutral. I only come out of my relaxed state IF she breaks one of the responsibilities. For example if I have asked her to trot and she is trotting then I stay still, quiet and just pass the rope around me. If she should walk or stop however I bring my life up and uses phases to remind her that she is meant to be trotting. Slowly she tries to work out what she must do to keep me quiet in the middle. When she eventually follows the rail I want her to go around the edge of the school with no input from the rider, thus transferring the responsibilities to her ridden life.