I'd love to know if there's a direct correlation like that in your question, Chris

If you strap correctly, then the draw will be almost completely a function of the strap itself, and of the razor. I've never used a strap or a razor that doesn't offer much draw, so I'm curious to know whether or not more passes are required on such straps than on straps that produce much draw. I doubt there's much difference though

If you know you can get good draw, but you're not getting it, it's a matter of strapping technique. When my blades are flush with my strap (and when they're sharp) then I get draw. If my blade isn't flush, then not so much. And if it isn't flush, I'm not using my strap very efficiently!