From my archives, here is a performance of me playing the Mendez favorite "Hejre Kati". It is from 1985, and it gives me a new goal in my practice: trying to get back to the double-tongue speed I could do then! The first hurdle is to get my tongue's muscle and speed back up. But along with that, one has to balance putting enough air past the tongue to get a pitch along with the percussive attack. I've heard a few players (some at the top of the heap) where I could hear the fast tongue but could not hear any pitch. On this recording I think I got some pitch with each. In any case, it felt like I was pushing it just as far as I could without losing pitch. As for whether I can that speed back today...
https://www.youtube.com/watch?v=hYVCDkD0NAk