This is a really good set of questions and an interesting topic that I would also like to learn more about.

My opinion on #2 is that composers and players will be all over the map on this depending on the feel they are trying to achieve. I'm thinking that the drums will be "centered" and be the reference for others to play on, ahead or behind. If everyone is playing behind (or ahead) then the band is centered. From what I understand, playing ahead or playing behind the beat can be subtle especially if you are a listener. Maybe the best way to discuss this is to look at the waveforms in a DAW. I'd be interested in what others have to say on this.

This video may be useful.

https://www.youtube.com/watch?v=TxTvZFaGGUs

https://soundcloud.com/user-646279677
BiaB 2025 Windows
For me there’s no better place in the band than to have one leg in the harmony world and the other in the percussive. Thank you Paul Tutmarc and Leo Fender.