Spending time around C.I.s makes it easier for a U.C. to pick up the slang of meth and its users.
A dealer might offer a U.C. a hit of meth to seal the exchange.
Sometimes a dealer will suddenly insist on changing the venue of a deal, leaving a U.C. without any backup in the area.
The targets were handcuffed and separated; the U.C. was also handcuffed to preserve his cover.