I just figured the chattering would stop because I've never really seen an altered dog doing it. But I'm seriously thinking I might hold off for another year or two then if there's a big chance of it messing with his temperament. It would really be sad to see all the progress he's made go down the drain just because I'm bothered by his teeth chattering.
Leo is neutered and definitely still sniffs pee and teeth chatters, though not so much anymore, mostly because I treat it as a behavior issue and actively discourage him.
It does depend on the dog though.
Last week, there was a standing in heat german shepherd roaming off-leash at the park. Owner nowhere in site. I was pissed. So irresponsible.
We had four dogs with us, including Leo. Since you don't exactly expect to encounter an off-leash un-supervised dog in heat, it took us a bit to figure it out, and we got a good idea on everyone's reactions. The intact male had to be restrained, because he was trying his darndest to get with her. Leo did not try to hump her but wanted to sniff and lick and was definitely chattering up a storm. Another neutered dog wanted to sniff a bit but was otherwise fairly uninterested.