Allison:
I realize there are issues and, like everyone else who can fog a mirror, I want it solved. However, until a viable solution is found, do I stay off the air? What's the purpose of the spec in the first place? It's to make sure that a transmitter does not generate signals other than the fundamental frequency above certain specifications (i.e., strength). But why? It's done to ensure that my signal does not degrade someone else's signal on some harmonic frequency. If you, or anyone else, cannot detect my harmonic signal outside my back yard, I may fail the precise specs of the law, but am still within the intent of the law.
In your own words: "...if one causes interference..." implies that someone is impacted by my transmission. If my harmonics are in the noise level, am I causing interference? Legally, with measures at the source, yes. To the rest of the world, no. For my stock ?BITX, I'm legal on 20M and above. On 40M, I'm 1dB out of spec. On 80M, I'm 3dB out of spec. I don't use 80M, other than contests, so that's really not a problem for me. 40M, however, is my favorite band. Not good.
I'm familiar with the word "denial" and I don't think you should imply that's what I'm doing. I'm not. I realize there's a problem, but unfortunately, I don't have the skill set to solve the problem. Your solution is for me to stay off 80M and 40M until you RF geniuses figure out a cost-effective solution. So why are you wasting your time bitching a me? Start pushing a pencil and show me the solution.
In the meantime, I promise not to use 80M...I'm pretty busy right now anyway, so I don't have much time for operating. However, if you hear my 40M harmonic, let me know and I'll cease operation immediately.
Jack, W8TEE