Yosemite Sam is just me being silly, Ken. For me it is JUST another measure of the top and doesn't really give any more clues about what must be done than does the distance between the FFs or the size of the endpin block or the width of the lower bout. Since I have the bass top off I can make these measurements and see what happens when i remove wood where I think it needs to be removed. I'll also be able to compare what happens when I cleat the cracks, and when I add the new bass bar.
The patterns are cool but are only a flag to show that the particular resonance mode has been met. I don't know enough about the shape to be able to draw any conclusions. And there are too many variables ... such as the arching shape for starters. The most interesting number I think is the frequency of vibration which combined with the weight of the plate is a measure of stiffness. If, after I do everything and re-cleat and replace the bass bar, the modes appear at the same frequencies, I can - I think - assume that the plate is fairly consistent with how it started out. If on the other hand, the frequencies are lower, but the weight is the same, this will show me that what I have done has increased the flexibility of the plate. I can make those sorts of observations.
I could - and will - also flex the plates with my fingers, tap them etc - and you DO get a lot of tactile feedback when you are working on the plates with the planes and scrapers. But this is more subjective.
Nothing here, unfortunately, will tell me whether I've done enough ... or gone too far!
See where I'm coming from? I'm not looking for a magic pill; it would be nice in a way if we could ****yse this work scientifically but I don't think this is at all easy - at the end of the day a luthier's work a series of educated hunches and generalisations. Some people might think that this sort of mucking around is a waste of time but for me, the more information I have to inform my instincts, the better.
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