Hi Brian
Sounds like an interesting project. I think just about everyone who has ever performed in front of an audience has consciously or in some cases unconsciously changed their persona in some way. It almost goes with the job as it were, wearing of seamen's caps, Arran sweaters, old-fashioned waistcoats, adopting a different accent, changing your voice in some way, playing up to audience perception, altering your chorus or speed of singing to accord with audience, the list is endless. Other genres perhaps even moreso, cowboy hats, dress suits, gypsy costume, gaiters, garish t-shirts, Hawaiian shirts etc. The dancers and mummers have always done it, so why not the singers?