9 & 3 is superior if you think about it, as it is symmetrical and thus gives you the optimal control regardless of how much you need to turn either way. It's what we teach for both street car control and track performance driving (been a performance driving instructor for over 20 years).
That said, if someone absolutely has their heart set on 10 & 2, that is still better than 98% of drivers out there with random single hand steering placement, so it's ok.
The absolute worst is single handed cross placement (e.g. right hand on 10'oclock). Please never do that, you stand zero chance of being able to do a controlled quick correction or emergency manouver if you have to.
That said, if someone absolutely has their heart set on 10 & 2, that is still better than 98% of drivers out there with random single hand steering placement, so it's ok.
The absolute worst is single handed cross placement (e.g. right hand on 10'oclock). Please never do that, you stand zero chance of being able to do a controlled quick correction or emergency manouver if you have to.