As for ranging with a reticle..... No. At least not with any semblance of accuracy. Has it been done? Yes. Can it be done? Yes. However, batting averages will be mighty low.
Well, a guy at least needs to know how to do it.
In the field on game during conditions when a rangefinder won't function (when it's raining, snowing, or just a mist in the air) is an example. We "know" the size of the target as approximate and can at least use the ranging function on our ballistic program. I know I would in those conditions on a hunt if I saw something that I wanted to shoot.
As far as accuracy, I guess you'd be surprised since you say it can't be done with any.
At just about every Tac match in the country there will be a stage that requires the shooter to range targets without the use of a laser rangefinder. We do it frequently at our monthly local shoots as well. The stage may be one that no shooting even takes place; everyone just lays down and does the exercise on the targets and records their calculation on paper and hands it in as homework. It's graded and scored.
The guy who won the stage at the SHTRC ranged every target within a couple of yards.
Sometimes we have to range under time then engage under time to be graded
