[Dr. Evil]

Assumptions:

1. Target type is known.
2. Range to target is known.
3. The number of mils the target would subtend at current range and AOB = 90 is known.

The question is, am I right in assuming that the arc sine of the number of milliradians the target ACTUALLY subtends divided by the number it SHOULD subtend at AOB = 90 is, in fact the true AOB? AND, is this a workable method of doing this?