Originally Posted by
Walter S
I think once you have some experience with similar loads and grades you can forget the math and just go on the basis of that experience. I'll learn a lot just from this trip next week.
That is the real answer IMO. Also remember if you run out of lower gears walking is always an option and if you find a 24-34 not low enough, it is steep enough that walking won't be that bad of an option.