If you think about it, a radar trap should be for speed control, not generating money for the police departments. Flashing your lights can slow motorists down and fulfill the purpose of a radar trap without having a ticket issued for speeding, or flashing your lights. A side issue is police departments that may have quotas for tickets and send their personnel out to generate tickets, whether radar is used or not. There are some notorious roads in Central Florida where the speed limits are way too low for the volume of traffic that use the roads. When the respective police department do patrol these roads, they're doing it mainly to generate income, not to slow people down, as they're not present most of the time; only when they want to write tickets.