hmmm...
46 in a minute is not much really IMHO. I remember doing 44 ages ago, and was only a punter who enjoyed training for climbing 6a's. no kipping obviously.
when I only had a fingerboard and a pull up bar to train on, to vary the training and fight the boredom I'd train pure power and "speed" power.
so I'd do sets of max number of pullups in 10 seconds on an edge. I could do 12 in the first set, 11 in the following many sets, and so so with a slow decrease.
so I think that for some dedicated trainer it's easily attainable a number around 55-60 even more.
what do you reckon?