well, I suggest to not eat nuts just before playing but if you do rinsing with beer or spirit (or water) will suffice.
It is absolutely pointless and overkill to brush your teeth before playing. I have neved done any such thing and my horn not only doesn';t smell but if there is anything in it ( like dust) it didn';t come from me.
I don't really think it matters unless you gulp down a big piece of chocolate cake and don't flush afterwards with a beer directly before you play. But if you have pieces of meat stuck between your teeth or maybe some other food residue, you should brush your teeth just for your own sake and the sake of your teeth. There is nothing worse than playing a solo and having to stop in between to pick your teeth when all eyes are on you.Probably due to hygiene on the reed. If you play with a mouth unwashed it's more likely to leave sugar residues on it and become a medium on which bacteria and fungi grow. The same for the neck I assume.
Sure, but you are proposing a conclusion that's overly broad based on the evidence you use to support it. Who's to say that your anecdote is more representative than other's anecdotes, and which anecdote is the rule and which one is the exception?I have never had ANY gunk in my saxophone, ever, if others do it’s not clear to me why , I simply don’t hav ethat experience ( I play almost every day). I clean the sax and swab it and never had ANY dirt on the swab worth noting. Since I don’t brush my teeth before playing I conclude that it is pointless to do so because no ill effects EVER came from not doing it and my saxophone couldn’t be any cleaner if i did. The only “ dirt” that I have ever found was a collection of little dust at the bottom of the bow but that was not food, I can promise you that