Yeah it's old news, but an awesome way to get the harder ones.
Most are dead easy, and it's faster to just run them down, but there's a couple (one in Nassau for example) that require better coordination and timing than I possess.
In those circumstances it's WAY easier to identify the exact pixel the Shanty spawns on, go there and make a cuppa or whatever, it only takes a minute of two for a Shanty to respawn. :)
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"I wear the cheese, it does not wear me." That guy with the cheese (Buffy).