i mean, 'furtive movements' for real? that's probable cause for a pat down?
No, it's not probable cause because officers don't require probable cause to perform Terry pat downs. When an officer has reasonable suspicion that crime is afoot and intends to question a person(s), and that officer has reasonable suspicion the person(s) may be armed or dangerous, the officer may pat down outer garments for the purpose of discovering weapons (WEAPONS, NOT drugs) for the officer's safety. USSC decided this shit eons ago.