I'd never play the Rotta that slowly.

I had sacrificed a little bit of speed for the sake of accuracy when I made the recording. It is better to play a little more slowly and remain in control. I can play it faster and do at home but I wanted to avoid obvious errors on the recording. BTW, I used a Mollenhauer dream alto played up an octave from the written notation.

Interestingly (in response to Suibhne) it is thought by some scholars that the collection in the British Museum MS, although based on dance forms was probably for listening rather than dancing.

My argument about tempo is not that I think they are necessarily wrong but rather that too many pieces in succession at the same high tempo becomes wearing on the ear. Nevertheless, I do think that playing very fast loses something in the musicality. I felt that to be the case in Ensemble Unicorn's version of Tristano/La Rotta but not in some of the other pieces. This is, of course, a matter of personal opinion.

When it comes to speed, then I would think what you hear from Unicorn et al is exactly what you would have heard from the musicians back in the 14th Century.

We don't know that and never will.

However I do think that there would have been musicians at that time capable of playing that quickly. Of course, just because you can does not mean that you should :-)