To me, there should be a classification of HD as a "Secondary Service". If you treated HD as an FM translator or LPTV, if it caused actual interference, you could just use 74,1203
(Changes to HD from FM Translator/booster in bold
§ 74.1203 Interference.
(a) An authorized HD transmission will not be permitted to continue if it causes any
actual interference to:
(1) The transmission of any authorized broadcast station; or
(2) The reception of the input signal of any TV translator, TV booster, FM translator or FM booster station; or
(3) The direct reception by the public of the off-the-air signals of any authorized
broadcast station including TV Channel 6 stations, Class D (secondary)noncommercial educational FM stations,and <deleted> FM translators and FM booster stations. Interference will be considered to occur whenever reception of a regularly used signal is impaired by the signals radiated by the FM translator or booster station, regardless
of the quality of such reception, the strength of the signal so used, or the channel on which the protected signal is transmitted.
(b) If interference cannot be properly eliminated by the application of suitable techniques, operation of the offending [b}HD transmission[/b] shall be suspended and shall not be
resumed until the interference has been eliminated. Short test transmissions may be made during the period of suspended operation to check the efficacy of remedial measures. If a
complainant refuses to permit the HD licensee to apply remedial techniques which demonstrably will eliminate the interference without impairment to the original reception,
the licensee of the HD station is absolved of further responsibility for that complaint.
(c) An HDstation will be exempted from the provisions of paragraphs (a) and (b) of this section to the extent that it may cause limited interference to its primary station’s signal, provided it does not disrupt the existing service of its primary station or cause such interference within the boundaries of the principal community of its primary station.
I only bring this up because it already exists. I suspect it's WAY too logical to actually be considered.
Now it looks like the subject HAS been changed. Sorry...
Clouseau