Some players switch back and forth, but this isn't advisable. Here is a link to a resource that shows a case study of what this looks like and the sort of problems it can cause. Again, I'd have to see exactly what you're doing, but I suspect that when you're trying to switch between upstream and downstream you're really doing something that doesn't really reflect this difference. And remember, what works best for you depends on your anatomy, not who you're trying to play like or what mouthpiece you're playing on.I do agree that you can switch back and forth but for me, upstream is nasally, pinched and whiny sounding.
This is, probably, the predominant way of teaching embouchure to brass students. In my humble opinion, it's better to be informed about the different embouchure types (more than simply upstream/downstream), how they differ from each other, and what sort of instructions and practice methods are best suited for most players of each type.IMHO, the best is … to stop thinking and analyze too much : just put the mouthpiece on the lips and let nature take its course. And play !
It was probably just one of Donald Reinhardt's mouthpiece designs. There's nothing inherently special about them that makes one "pivot." Most people don't understand what Reinhardt meant by pivot anyway (he didn't mean tilting the horn). Here is a resource that describes what he meant.I was introduced to the system by accident when I was looking at a weird mpc on e-Bay that said it was a"pivot" mpc.
Paralysis by analysis means either you don't know how to analyze what you're doing now and what you should be doing (so it screws you up) or you're trying to analyze when you should be making music. This is why we have teachers, to help us with the analysis. Listen to what the best teachers do, not what they say, and you'll note that they frequently do the analysis for the student while telling the student to not analyze. If you want to teach or want to offer advice, spreading the "paralysis by analysis" myth is missing the point.I think "paralysis through analysis" is a definite possibility here
Arturo, by they way, fits within Reinhardt's Type IIIA embouchure type. All players have an embouchure type (or types, if they switch between more than one). It's not a system that you choose to fit inside, it's a way of classifying basic embouchure patterns that simply are. Again, the point of doing this sort of analysis is to know that if you properly should be playing with the same embouchure type that the way you should play would resemble that of another (all players have differences, though). If you're not already experienced with this you should get the help from someone who is, otherwise you're probably better off just playing and not worrying about it. If you mistype yourself you could end up trying to play exactly opposite of the way you should be playing.I wonder if Arturo studied this while being raised in Cuba?