New to this website. At risk of sounding foolish:
One secular thought about successful public band performance psychology is creating "tension" with the listeners (crowd). If you create "tension", you engage the listeners. Creating tension can be done by many means such as total silence, noise, suprising, deceiving, boring, puzzling.... Once you have engaged the listener, you have got them on the train and you can now take them to the next station. You resolve the tension with the intended musical or spoken message.
For example The "Phantom of the Opera" musical stage show does this by having the first 7 minutes with poor lighting and poor audio. You are thinking to yourself, "man, did I pay real money to see this?, I can't see, I can't hear,,, get me out of here..." You strain to see, you strain to hear,,, Then all of a sudden,,,,Boom, off go the blinding fireworks, the organ plays thru the million dollar PA, and the chandelier lights, rises and then you are hooked for the next 2 hours. You want to see what happens next.
Our mission as church organists is to engage the listener in the music to take them to the next level. I routinely use many techniques to create tension with the congregation. The leslie rotor offers one tool for the organist to create tension in the music. It also offers a way to communicate to the listener that a change is going to occur,,,(key change, verse, chorus, ending,). Thus use of the switch is situational and depends on the piece.
As an example of interplay between sound & psychology, see an interesting write up on film sound at:
http://lavender.fortunecity.com/hawkslane/575/theory-of-film.htm