Don't bet on cops not being able or willing to leave their "beat". What do you think is gonna get him more atta-boys, a traffic ticket, or felony arrest after a consensual drug search? They're ready to carry someone to jail on short notice, they'll have no problem taking time off in the very near future.
And, what do you think the judge is gonna do when you come rolling up in his court, out of turn on the docket, with a cop who says all the right things? I wouldn't want to test it without video evidence I did not commit the offense.
And, with tons of defense lawyers and websites with advice on how to beat traffic tickets, if this technique was all that successful at dissuading cops from writing the ticket, the information would be all over the place by now. Take the provision about hand-service for redlight camera citations. You don't have to look very far to discover advice that you can ignore mailed redlight camera citations.