Feature Reprojection Error Threshold?

I’m suspecting that mean and median error are not a measure of Alignment quality, but simply the mean and median of the long-tail distribution curve that results from any large sample of points, ties or whatever - and that curve is pretty much the same every time. Those typical 0.3 to 0.5 numbers seem to remain in the same range under all Alignment settings, with two exceptions -

One is with very poor small photo sets, where there’s a significantly small no of points, ties etc, so the distribution curve differs from the well fixed large-sample curve;

The other is under influence of Max Reprojection Error, which applies a top-cut to the long tail of the curve, hence mean and median shift close to the peak of the curve.

Think of it as a set of four figures - minimum, mean, median and maximum (minimum in all cases being zero or v close to).

So, really quite uninformative. The need to get Alignment mean and median error under 0.5 is meaningless, as it’s always that under almost all circumstances.

True or false?