Steering wheel posture

I sit low as the seat will go and hold the bottom of the wheel.holding the top seems to kind of exaggerate the slightest movement compared to the bottom.to me anyway.

 

I don't think a blown tire would jerk the wheel hard enough to break a bone.
That said, I have a titanium plate on a bone in my left hand that was broken when I was in an accident with another vehicle. So maybe your trainer has a point.

 

I'm not sure how long you have been trucking. Back in the old days the tires were not as good as today. Plus drivers were in cab overs. Those steering systems were nasty and unforgiving. I have seen broken and misshapen thumbs several times now. If you have been around trucking for over 50 years and remember these drivers like I do you will respect just how violent those blowout jerks can be.

 

Started driving in 1986. I agree that on the old armstrong steering it could happen. I have never blown a steer but with power steering I would think it is controllable. But I could be mistaken!

 

Of course with the new and improved trucks, tires and suspensions/steering systems this is not much of a hazard any longer. However I think it would be foolish to just drive and totally not respect how violent a steering wheel can be jerked because steering system parts can be defective and or broken during the actual event. I always held my wheel with my left hand only (I know not taught to be correct) while driving at speed with no real direction changes expected. Then 2 hands when driving on city streets. I always held with my palm on the outer part of the wheel and my thumb on the front edge of the wheel facing me. I only put my thumb on the inner part when going slow and making large amount of steering wheel turns.