In last week's MCN (only just got to see it), and article based on FOI requests to police forces who use unmarked bikes.
Oh dear . . .
OK, so no details of what incidents they were involved in - but they're not short of them! [And, just a thought, it doesn't discriminate for (if) any used in non-'traffic' type covert work]
Doesn't help for any trainer suggesting that 'police techniques' are the way to go . . .