Okay, I'll put in my 2 cents. This whole system, I suspect, was invented by Tony due to his obsession with "equivalent" f-stops for different sensor sizes due to depth of field. His system does not make sense to me for the following reasons:
1. milliseconds for shutter speed seems pretty straight forward, until you get to shutter speeds faster than 1/1000. The you have things like .625 for 1/1600th or .125 for 1/8000, etc. This is not going to be any easier for a beginner, IMO. Also, if you want to move in 1/3 of an f-stop, the numbers get goofy:
1/1000=1 ms
1/800=1.25ms
1/640=1.56 ms
1/500=2 ms
2. His system trades a constant ISO value between sensor sizes with one that has to be converted for every sensor size so that his goofy "equivalent depth of field" aperture system works for exposure.
3. T-stops can't be used to calculate depth of field. Only the area of the opening in the aperture, the true f-stop, can be used. The differences might be small, but important for critical work.
4. Dividing the ISO by 10 to create a supposed easier number is silly. 80 is no easier than 800. 64 no easier than 640.
5. The system we use now works just fine. People who are really in to photography have it down pat. People who are casual about photography will likely never bother to worry, setting their cameras on automatic, and phone users could absolutely care less.
I guess I don't have a problem with using angle of view for describing lenses. I would still want to know the true focal length of the lens too, though. That, combined with the true f-stop, is the real way to calculate depth of field.
Anyway, Tony will hammer this equivalent f-stops between sensor size thing forever, I suspect.