I had a six-hour session with an older 'ler, he was very experienced. I was restrained spread-eagle and he used everything on me - paintbrushes, a hairbrush, feathers, electric toothbrush, fingers. I had a few small 2-minute breaks just to breathe, but wasn't let out of the restraints. It was a lot of fun and I do think my endurance came from being tickled a lot by boyfriends and friends.
Tennessee huh? Shame about that whole geography thing.
Just gotta say, post-orgasm tickling is THE. WORST. TORTURE. Everything feels at *least* twice as sensitive. And five minutes of that feels like half an hour! I could handle 6 hours of normal tickle torture but post-orgasm would break me in less than an hour.
My longest tickle session was about 2 hours with lots of breaks. I was tickled by 2 ppl so it was definitely intense! I don't think tickling is something you can learn to endure *at least for me* Ive had dozens of sessions and I still react the same way for every single one.