Commentary attributed to Mitch Rubenstein and posted here by Aaron Gjerde:
"The Secretary of the Interior’s Standards for the Treatment of Historic Properties are regulatory only for projects receiving Historic Preservation Fund grant assistance and other federally-assisted projects. Otherwise, these Guidelines are intended to provide general guidance for work on any historic building."
Except for projects receiving federal funds, the guidelines are just that: guidelines. Most of the content of the Department of Interior's publication regarding features, materials, and procedures consist of things that are recommended or not recommended. Again, the key word is recommended, which implies discretionary, not required.
It seems that if the intent of the HPC's proposed rules is to prescribe in detail requirements for various projects, then HPC would be 1) deviating from the intent of the federal guidelines; and 2) prescribing things that Department of Interior left as discretionary to property owners and project directors. In the same vein, detailed regulations by HPC would make sense only if HPC were overseeing use of city grants or funds used for preservation, rehabilitation, or restoration.
[ed.] Indeed, providing access to funding for preservation work was an approach promoted by Jim Sazevich and others at the time of initial establishment of the HPC.