David, one often has to quiz non tuners about what exactly they mean. Ideally, you could meet with him at the piano and try a few things to see what he's talking about. I doubt it's one beat per second. My guess would be somewhat more, unevenly spaced, with a few assorted screamers but maybe I'm wrong. Pure unisons don't indicate anything about the intervals at all, which might be more germane but as I suppose you won't be using an ET scheme that might be adequate.
I associate the metallic tone with honky tonk more than the tunings.
Here's a video of Ms. Atwell playing a few different pianos, some are in tune and some aren't. The cottage piano is both out of tune and damping very poorly but that might have been a novelty piece, the others were pretty nice grands.
https://www.youtube.com/watch?v=dQlY6UoM_-E more her work follows this one.
I tuned for a well known touring honky tonk player here a few years ago, he performed on a nice Bosendorfer grand and had no requests regarding the tuning other than it be tuned prior to both performances. The out of tune honky tonk sound might be more of a cliche than a practice.
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
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