This is a very good question and is so very difficult to quantify. All we have are experienced, anecdotal, qualitative data from users on this, and other, blogs. Of course this is valuable data for sure, but what our hobby really needs is an scanning electron micrograph "SEM" of edges followed by some sort of quantitative cutting resistance that simulates whiskers. There are such tools for knives, but the edge of a straight razor is far to fragile to use them.

With that said, here is my anecdotal response.

I think that the stropping on leather is the single most important refining step to any edge, and that if it is being done right there is benefit up to 100 strokes beyond which I don't find and difference. I typically use 60-80 laps. I have always found it fascinating that most DE razor manufacturers stop at ~900 grit for the final hone on the micro-edge. Of course the angle and pressure are perfect. Out of curiosity I have tried a lightly honed razor right off my 1000 grit followed by CrO balsa then 100 laps of leather. It was an excellent shave virtually indistinguishable from my Naniwa 12k finish. What this means to me is that once the edge has converged perfectly, even at a fairly low grit, the refining stages of CrO and/or leather seem to be contributing the most to the comfort of the shave. Of course this is just a qualitative opinion.