I'd like to find out
G.W.L.T.L., no one has taken me to the level of getting tickled in the way you described since I was a small child. The most intense tickling I remember, something an uncle did to me when I was maybe 8 or 9 years old, may have lasted a few minutes. As I am primarily a dominant tickler, I know a few minutes ain't much as I've tickled a number of girls much longer without stopping.
A big part of the reason my uncle got me so good was the element of surprise, as he simply jumped me when I was resting on a sofa. In recent years, switching with or totally submitting to dominatrices in dungeon tickling sessions, knowing what was about to happen caused my defense mechanisms to kick in. Three skilled ticklers in particular still got me going pretty good, but in every instance the mistress relented even though I was not ready to ask for mercy.
I would like it very much if a girl with expert tickling skills could get me going with no plan to let up until I beg. I'd like to see if I could take what I've dished out so many times. Maybe some day my tickling princess will come.