Yeah, screw messing around with walls and measurements. I ride a bit, adjust, snug and go about my business. It ain't rocket science.
That said, the only light worse than the Rocket Touring light is the Tiger 1050. Fortunately, I can run my brights on the Tiger, see good (about the same as low beams on a car) and other cars don't know the difference. Most folks on the Tiger forum go with HIDs. Some do what I do and just run the brights all the time (at night).
I was beginning to think Triumph simply didn't/wouldn't/couldn't figure out a good headlight system, but then I bought my Thunderbird. The lights on it are FAR superior to the R3T or the Tiger. I don't remember how good the lights were on my old Speedmaster (too many years ago).