Is the doctor doing mainly metal abutments or Zirconia abutments also? With metal abutments (gold or Titanium) we can make the abutment as thin as we need it and not have to really worry about Dr's breaking the abutment when torquing, the screws on the other hand is another issue. I have had some Dr's that have overtorqued the screws and the screw head broke, and then your there trying to explain to the doctor how to remove the broken screw.
Reason i asked if the Dr is using Zirconia abutments; is if the Dr hasnt been torquing them properly and the zirconia abutments have been designed to thin, the abument may fracture after the proper torque.
Also if the Dr is doing multiple units , preferably in areas where esthetics are not a major issue, try recommending to splint the units to minimize screw loosening.
For some of our doctors, weve gone ahead and bought torque wrenches and when a Dr doesnt have one , we have them put down a full payment on the cost of the drivers to use it, they just pay shipping and handling. If they dont return it or they decide to keep it, the investment on the driver isnt lost.
Hopefully some of those ideas help out.