Duo
I've been on both sides of this... I think I now work/live the best way...
1. Require the time from your techs, or (as I've had to do) sit there and watch..... boring but interesting (when you watch from afar it takes longer than sitting there). You soon develop more of a feel for time, and that is easily shared with the techs as a 'look it only took....'
2. Then require them for account for their time, at least to a WO. Let them know the time guidelines for a job, and give them an incentive for coming in under - i.e. you save 10% and you get a % of the sale on a recondition - I must point out that it's amazing how many parts they then decide can be refurbished instead of replaced, and the time that is saved.
3. The time limit is then part of the review process. As a part of their goals it is when in time meets expectation, etc and if under then exceeds and is in line for a raise.... You get the idea
4. The nasty bit is when the mechanics will not do their bit. This year I've had to replace all the mechanics at one of my shops who refused to account for their time. It's amazing how the rest got in line and on with the program, even nicer with the new folks - a breath of fresh air..
5. I know your on thsi forum often. We've all read and stated how a good technician is independant and accoutable, your problem would suggest your folks lack in these imprtant qualities...
6. When I started I trained in the shop as well as formal class room training. The senior shop techs kept the new techs and junior shop techs in line, they were allowed some ubilled time to do this. I learnt more from those folks than any school I ever attended. They were always a good go to resource. I've seen shops used as punishment - if your a bad road tech go to the shop etc. It's a culture change, have your shop techs ever ridden on the road, and seen what where how the road tchs have to do it. It's a unique business, and both techs can feel the other has it better unless there is true cross pollination..

Sorry If I rambled.