When I did the Sabreliner maintenance course, we spent a couple of days in the sim just working on taxi emergencies. In particular, the Sabre steering system has a potential hard-over issue, and we spent a lot of time focusing on dealing with that, as well as trouble shooting it. Interestingly, It didn't ever come up in my flight training for the Sabreliner.

Speaking as both pilot and mechanic, the focus in maintenance start and taxi is a little different than that for pilots. The basics are there; engine starting in order to move the aircraft, and the mechanic needs to look for the same start malfunctions and issues, and use the same checklist to get the engine started. Maintenance personnel usually have their own run cards and checklists as well, however, that address the additional myriad things that the mechanic should be looking for.

During engine start, you may not be paying attention to just how far the battery droops, or how high it goes during the recovery with a generator online, but from a maintenance perspective, it's important in understanding a number of points in the electrical system; what they're doing, battery health, etc.

Taxi is often new for mechanics. Mechanics aren't used to much of what we take for granted as pilots, including the potential for the aircraft to get away during an engine run (something pilots seldom do on most turbine equipment) the first time the operator goes heads-down. In maintenance trimming and troubleshooting, the aircraft may be operated at moderate to high power settings while holding the brakes, and unlike holding short at the end of the runway, the potential to do a lot of damage very quickly is high, if the brakes slip or the mech isn't paying attention outside the aircraft.

Likewise, the mechanic may not appreciate the effects of jet blast, as the operator, and while a mechanic is used to looking for FOD, thinking about it while focusing on doing an engine run is multi-tasking; it's something that must be relearned and discussed.

My preference is to have a pilot do runs while the mechanic watches and calls out what needs doing, but it's common at many maintenance facilities to have mechanics do power runs.

You indicated that your operation is not considering sending the mechanics to FSI for maintenance training. I realize that it's an expense, but it's a good investment and something that you should at least consider. The maintenance world is considerably more complex than the piloting world; most pilots understand that quality flight training is a very wise (and necessary) high priority investment, but often dismiss the same need for maintenance personnel.

When I went through the FSI program on the Sabreliner some years ago, it was the oldest sim training program running, and the instructor was the longest teaching instructor in a type program. He retired not long after. That kind of experience and instruction shouldn't be discounted. Mechanics don't get type ratings, but still need type specific training.