I googled the name and wondered if this was the Elvis impersonator I found. If so, why was he imitating Redd Foxx?
You're right, they're not. But every Elvis impersonator must get tired of The King's comparatively limited catalog (that they can get away with performing - those religious albums of his wouldn't fly) and start doing the hits of others just to break up the monotony.
And we arrive in the gray area again. If 'Elvis' plays it straight, it's not dementia, but if he doesn't, you get into a "Big Daddy" situation - a band playing new songs in an old style for laughs.
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Halfshell:
Doug Church is also an Elvis Impersonator /Tribute Artist, he did a couple of songs Like Billy Idols's "Mony Mony" imitating Elvis, I don't think these count as dementia type tunes do they?