I actually find that a decent argument, but I believe it’s already been shut down. When police used thermal imaging to “observe” a house, without doing anything they thought required a warrant, the Supreme Court decided it was too intrusive ( https://supreme.justia.com/cases/federal/us/533/27/#tab-opin... ). But if I understand the ruling correctly, if the police make it well-known that they have the ability to do something intrusive, then they don’t need a warrant.