It was the word "advice" (that I underlined) in my original comment that caused me to ask my question. However I now note that "advice" only applies for deconfliction purposes.
Is the ATC unit not the 'Controlling Authority' for their Procedure and therefore perfectly able to give Clearances to those aircraft that have requested to participate in their Procedural Service?
They would certainly (as Gertrude suggests) be entitled to say "Procedural Service Terminated - Advise us of your intentions" to those aircraft that refuse to abide by their terms.