I did not watch the video, but I know the recording of Mandria, one of my favorites of D'Arienzo. If you are referring to the tempo of the recording, it's worth checking out. I believe you will find it doesn't pick up speed. It is strict tempo.
I recall an Australian saying that a vals picked up speed at the end. I asked him to listen at home and check it some way. He confirmed that it sounded faster, but the tempo was constant. More notes may sound like a faster tempo, but it's not.