Are any of these around? Online? I have my old Cloos piccolo up and running and I’m noticing some interesting things - for one I’m commiting myself to placing the pads of the fingers straight down on the holes, like on a Northumbrian pipes chanter - flat against the body and you tend to bump into the short F key, even though Cloos made it very skinny. At least, when you’re gracing the hole it happens - very touchy there, you can easily squeal the F# into a high C#.
Also the best place for the left thumb seems to be on top of the Bb key pad/hole - you rock the thumb ever so slightly back and the key opens. It’s much like the grip on the flute proper then, with your index finger angled towards the flute’s bottom.
I’m just curious if this is how the pros did it. Piccs are quite the hoot/toot.