[davorak]

50% is an easy first order approximation. Better approximations are great, but I see not obvious winner for a better approximation whose error bounds do not include 50% and has or is likely to gain significant mindshare.

[wfunction]

"Easy first order approximations" are good starting points, yes.

We've started at that point many years ago; we should be trying to refine our easy first-order approximations instead of living with them forever.