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I do, however see the utility of the "RFOV" concept. it allows you find an equivalent field stop and predict the true field of view of an eyepiece in any Telescope, even if you don't have access to the written specifications.
Here are calculated "RFOVs" for the various Nagler eyepieces: 77.6, 77.1, 81.0, 78.5, 81.9, 79.1, 77.6, 81.6, 77.6, 78.9, 79.4, 80.2, 78.6, 77.9. How are these numbers easier to use in the field or elsewhere than the effective field stop diameters that Tele Vue quotes?
As far as I know, they are not easier. Maybe it is because people almost always see the old TFOV = AFOV/Mag formula and then get hung up on using that particular equation rather than the somewhat lesser-known but more accurate TFOV = 57.3*EFSD/Fl formula (EFSD is eyepiece field stop diameter and Fl is telescope focal length). Clear skies to you.
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Re: Strange Results in Eyepiece FOV Comparisons