As a guard trainer, I never use it (maybe a little bit to round out a player). I imagine it would be a very useful training type for a big man trainer.
The reason I don't train it is that handling and driving pop with most training types. With my current mob of trainees, I haven't specifically trained driving or handling at all, but they are pretty well keeping pace with their other skills.
That said, driving in particular is probably an underrated skill.