When considering an adjustment to development of negatives, one thing we seem to consider is the Shadow to Brightness Range. I thought this was like a spot metered Shadow EV of 6 subtracted from a Bright EV of 13 giving a SBR of 7 stops. From that 7 we would make a personal discission whether or not to adjust our development time and by how much. Perhaps the 7 is a lot, perhaps a little or perhaps no adjustment is needed.
It dawned on me that this may be the wrong way to approach the question of +/- development. If we believe in the tenant of "Exposure places the shadows and development places the highlights", then shouldn't we consider adjustment to the highlight portion of the spectrum because the shadow portion is not going to be altered regardless? In the example of EV's 6 and 13 suppose the mid-gray were 11 EV, wouldn't a better conclusion be that you had 2 stops to consider?
I think this would be important in low key photos where you have an image of long toe and short straight line.
Perhaps you see no merit in the question but these kind of things bug the heck out of me.