The cops, motorcycle or squad car, sit out of sight on major thoroughfares like Dublin Blvd. and Dougherty Rd. and watch the cars going by. You can't see them first. They see you first. Usually they are hidden next to a building or other obstruction and watch you go by from a perpendicular angle off to your right. It is like shooting fish in a barrel. No chance to avoid if you are on the phone.
I work in Dublin and have been witnessing this going on for quite awhile now. Lot's of cars pulled over and ticketed. Probably not too many Pleasantonians have been victims, but I think Dubliners along with the commuter traffic coming from Windemere/San Ramon driving to access I580 are the central victims.
When and if the Pleasanton cops catch on how easy this is to enforce, watch out!