"actual testing at range will often illustrate that the ballistic calculators are not a reliable estimator of trajectory."
I have found just the opposite. The ballistics programs are excellent trajectory predictors, at least all of the ones I have owned. The secret is to not use the default settings. To have them accurate you must plug in all the actual values for things like:
scope height, measured muzzle velocity, altitude(very important), temperature, barometric pressure, humidity, etc.
Even at 1000 yards every program I have ever tried has been within 1 MOA, usually less.
Jack