A swarm can occur in a single place or can follow a person down the street as they approach a known destination. This is accomplished using a choreographer who follows me and cues provocateurs to suddenly step out from around corners or from out of door ways, etc. in an attempt to trigger an observable startle reflex, i.e., a visual double-take.
They can also cue people to walk ahead of me forcing me to be exposed for prolong time to the visual harassment, which of course, induces anger. (see Red Sunglasses)
Choreography is also used to cause someone to position the target in a desired location. For example, the group may fill up seats at a bar then as I approach, one exits leaving a seat for me beside the provocateur who will elicit me. The same thing is done to ensure I get a parking spot. One of the perks, I suppose…
These tactics are believed to have been developed by researchers for use by law enforcement Special Surveillance Groups.
Street theater and the Raging Grannies
At least one woman has been tentatively identified from this group in a harassment event. Numerous photos of the groups online show them wearing the floppy hats and sunglasses often used in silent swarm harassment. http://www.raginggrannies.com/
Special Surveillance Groups