That's a tired old argument, because there's dragons then nothing else from reality need apply. We aren't dealing with a setting created by Salvador Dali where any fantastical nonsense could exist. We're dealing with a world where even the most fantastical of creatures is defined, and how it interacts with the world is known. To argue that there should be no reason to model real world tactical concerns like unknown distances because there are ratmen in the game is nonsense.Furthermore, we're not meant to be playing a simulation of historical battles - we're supposed to be playing a tabletop strategy game in a Fantasy setting.
Your argument makes even less sense when you consider that in previous editions there was still an effort to model these unknowns - that's what banning premeasuring was about. The problem was that most players within about a dozen games could eyeball ranges very accurately - as a means to include some kind of fog of war it didn't work.
Only if we assume troop movements are as they occur in the game are exactly as are occuring in the fantasy world. So a unit trying to make a charge across 9" is trying to make a charge across 90 yards in the fantasy world, and a unit trying to make a charge across 15" is trying to make a charge across 150 yards in the fantasy world.No, it probably isn't realistic for armies to charge successfully every time and remain in formation. However, nor (IMO) is it any more realistic for them to stop a quater of an beyond the half-range of archers/crossbowmen. Furthermore, I'm happy to sacrifice realism (especially in a Fantasy setting), if it means having full control over my army's movement.
Except we know that isn't true, and that ranges and turns are an abstraction, because if we apply historical weapon ranges to WHFB, and then use that to determine distances, and then note how fast troops are travelling between weapon volleys, the answer is complete gibberish.
The whole thing is abstract. Instead of thinking 'they tried & failed to charge across 8', think of it as 'the general was informed they were in good charge, and signalled they should proceed, minutes later he was informed the unit took some time to gain cohesion, and the target was further than estimated, and they are now regaining cohesion for another charge'.
You said there was no upside. I pointed out that you can make unlikely charges just as often as you can fail likely charges.So, the benefit for random charge range is that you can deliberatly select an unlikely charge range and hope to roll that double-6?
That's just what it is. It used to be you could charge 8" (or 10", or 14" or whatever). Now you have a range in which you might make a charge, with a mean in the middle, and anything below that is a charge you should make (and therefore a risk you might fail what you ought to achieve), with anything above being a charge you shouldn't make (and therefore a chance you might succeed where you shouldn't).