Quote Originally Posted by pentaxuser View Post
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.
Two things: before C41 was invented, other processes were used and these could be run at room temperature. So no, you don't have to run all possible color processes at 38C, but C41 was evidently designed for operation at this temperature and will not work well above or below 38C. It's all how you design the process. Note that such a process consists of emulsion and developer, so there's not much we can do about this.

And second: b&w doesn't have the issue with color balance, so you could, in theory, run a b&w process way beyond 38C. What will prevent you from actually doing this are the resulting extremely short dev times and in some cases considerable softening of the gelatin, but not the process itself.