I'm not Rebeckah but thought I'd jump in.
I'm a visual person so bear this in mind.
The first time I mixed the P&B shake I did it wrong. Didn't mix the ingredients in the correct order. The stuff congealed instantly in the glass. Adding more water just made it globier. No way could I gulp that down unless I used a knife and fork (someone pass me the ketchup please!)!!
I tried pouring it down the sink but it wouldn't go. Had to break it into little globs - water did not dissolve it. (Yerba and Sonne)
As I looked at this glob, I thought of my intestins and the effect it would have. What if I drank it and it just sat there? I'd be seriously clogged especially if I hadn't done a full Master-Cleanse to begin with. While on the Master-Cleanse the only "food" that could push this, is liquid. How much strength is in that? SWF, teas and an enema would be the next step to remove a blockage which I have needlessly created. Oh joy!!! ha ha
Now the P&B is stuck and you're constipated. Which means toxins are not being released from your body rapidly but sitting in one lump. The lemonade is trying to clean but hits this blockage and so more toxins are being accumulated, concentrating in one spot. Your body reacts by making you feel ill. Next thing - you want to quit the fasting.
A fast is difficult to begin with, why add more complications to it? See my point?
The Master-Cleanse is preparing you for the next step - ridding parasites. I think it should be used in its purest form - without any additives. It then concentrates on cleaning you and is not detracted by the P&B.
Bentonite is a detoxer. Psyllium helps move the bulk along. What bulk do you have while on a fast? Is water bulk? (only if frozen!) This is why "I" think the P&B shakes should be taken while doing a parasite cleanse. Water and FOOD will help the P&B move along faster and detox your body consistently, regularly.
If I had mixed the shake ingredients correctly I may not have come to this conclusion.
You can always try the UF and see how it goes for you.
Whatever you do, stick to the guidelines!