Well, thank you for having me.
   No, I don't mean the word "fast" literally. But I do make Sapo the first important thing I do during my "fast", and don't eat before the medicine. I also consider the medicine all day, so that it becomes a real focal point for me. And the daily cleansing seems to have a really good effect on my overall physical/emotional/spiritual state for weeks afterwards.
    Tamishi can come in all sorts of sizes, and obviously three burns by one with a 1/4 inch diameter is very different than 3 burns with one with a 1/8 inch diameter. So sorry if I was unclear. And I know I just judge the number of burns by the size of the tamishi, along with knowing how potent the resin is: I generally test that with just a touch to my tongue. It varies in at least three ways: by how the frog is caught, how much sapo/kambo is extracted from the animal, and how recently the animal has used the resin to protect itself.
    For instance, most Matses collect the branch on which the frog is sitting and never touch the animal until everything is ready for extraction. Done properly, the animal will never have felt threatened and so will have all of it's most potent secretion ready to do. If the animal is frightened at all and releases some sapo, then whatever else is collected will not include the most potent medicine. You need to think of it like this: The frog's primary predators are constrictors, most of whom have no venom (though there are some rear-fanged constrictors). They take the frog into their mouth: The frog has a split second or two or three to release the sapo into the snake's mucous membrane, which freezes the snake and allows the frog to back out of the mouth. If the frog is slow, it will be crushed in the snake's throat in very short order.
    Which doesn't mean that there won't be more sapo once it's free of the snake, but it won't be at the most potent level. Just as a snake can be milked for venom even after it's killed an animal for food, it's just that the venom isn't ready yet, isn't full strength.
   So, if the animal has been frightened or touched when being collected, you're libel to have a stick of material that isn't very strong.
    You'll also have a stick that isn't very strong if the frog has been frightened even a few days before you collect it: It takes several days for the resin to become full strength after use.
    And then, of course, some collectors try to get quantity out of a frog, rather than quality. When Pablo, Alberto and the other Matses men who really depended on sapo to help in hunting, they'd sometimes use three frogs to make a single stick. I still have a little of that material--some of it 15-20 years old, and it doesn't seem to have lost a thing.
    Anyway, to get to know a given stick I flick my tongue on it: the reaction that comes pretty instantly lets me know what kind of material I'm working with and whether it's gonna be a 2-3-4 burn day, and how big the burns should be.
    So yes, tamishi varies in size.
    Sorry for that long long response to something nobody asked. I just get started sometimes.