We have to deal with existing atty designs & the only thing we can vary is the thread design. While your variable draw sounds interesting, it's beyond the scope of this design. In a nut-shell, we either bury the atty air holes in threads that run to the top, OR recess the threads. This will be ONLY for 510's. If you look at the Joye design, the threads are RECESSED to allow access to the atty air holes. That is the ONLY question - to recces or not to recess, that is the question. Frisco: Your missing the point. The limiting factor is the air holes IN THE ATTY ...can't change that. All we can do is allow more or less access to these air holes by reccessing or not.