Yes the point I was trying to discover and PE and others seem to have confirmed this is that the high temp of 38C and quick development isn't simply "time is money" driven. It is inherent in the process and likewise it would seem that in B&W there is a limit to what can be successfully done at very high temps.

So the extrapolation of a line whereby dev time is shortened the higher the temp used, eventually breaks down no matter how much the "time is money" arch capitalists would prefer it not to