Seems easy to monkey wrench
I don't support destructive protests, but this "scent bank" idea plus all the dog training must be costing quite a bit. And it seems the plan might so easily be disrupted...
What happens if everyone who thinks [dawn raids, very subtle] they might have, umm... been sniffed, trades 3 weeks of their dirty clothes with a number of grandmotherly protesters? Or collects 50 pairs of unwashed socks and distributes them for people to tie around their belts?
I wonder how much a radical shift in diet for a week, plus shaving all your hair (old scent in that, presumably) plus living in a different location for that week would change one's scent?
All the protesters dust their pants with cayenne pepper? Would a snort of that put a dog's nose out of commission for a few hours/days?
And so forth.