I think disallowing pre-measuring is a clunky game mechanism because, as the OP says, in an age of professional officers, estimating distance and effectiveness is part of the job. On the other hand, it does mean that occasionally players will misjudge and thus lose unit effectiveness. There are numerous historical examples of troops firing too early, chargers misinterpreting the roughness of the terrain, etc. And, occasionally, this has affected the outcome. So, I can see range estimation as a way of simulating these small details which may not be represented in the rules, per se.
Personally, I’d rather see some variability in charge distances and range modifiers to cover these factors. But that’s just me. I’d play games either way.
Self taught, persistently behind the times, never up to date. AKA ~ jeff
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