Jack -

Not worth a quibble, but the "percussiveness" is only apparent in a few languages, and in the more general cases the phoneticists say there's no difference except one being voiced and the other non-voiced.

In phonetic notation, there's an additional "mark" to indicate addition of the "percussiveness" to any stop, as opposed to an "ordinary" version of one. The usage indicated by that mark may be common in your circles, but isn't often used in most of the examples where I've looked for such differences. (N. Chomsky taught a fairly interesting course in linguistic phonetic notation, and I always he assumed he made the marks in standard fashion and had a decent ear for the subtleties.)

In my younger days I did notice that the flutists in the band (all female in my acquaintance then) seemed to have "exqusitely seductive lips" so maybe they do speak differently. If so, I would need to apologize for dismissing the characteristic in those I knew as just representing an unusual selection of "specially gifted" persons.

Perhaps if that one I thought might be the most appropriate subject had been more amenable to my suggestion(s) about studies involving appropriate "lip tests" I'd know more on the subject, but ....

John