on your first Gearslutz Q+A you mentioned how Rick Rubin requested a dry upfront vocal and most everything else hard-panned. Reading this was a major reason for me to go LCR, it was like a final confirmation after realizing how many classic albums were mixed that way.
Are there elements in a mix that you usuallay don't pan LCR? Are there bands or producers that request a different panning approach and/or is this ever a point of discussion in your work?
I guess I'm lucky in the sense that for the last 20 years I've been tracking and mixing on a console that only gave me L-C-R in the monitor section. My old Neve 8038 has been modified to allow for panning in the expanded mixing mode, but the hard choice of Left, Center, or Right was imprinted into my work flow.
There are a few things that I will place in those spaces between the center and hard left or right. Hi-hat I will usually place just off-center to the left. Toms I will often narrow the span from high to low so the power of the drums is mostly coming from the center.
A single acoustic guitar and vocal together could typically sit in the center of the audio picture, but I might offset the acoustic to let it come out from behind the vocals a bit.
I might fill in those middle spaces more dense and busier mixes, but usually with more airy sounds, keeping the power and punch coming from the center and far panning positions. I have enjoyed using 3-dimensional processors to throw sound behind the listeners head too. On Tool's "Opiate" there is the sound of a phone ringing on the behind right side of the mix during a drums solo. Hah!