Is this site specifically for maintenance and repair, or are we going to allow questions about driving practices?
I agree that in general many driving questions would be off-topic for a "Maintenance and Repair" site. However, I think there is a certain subset of these questions which may be more relevant, and perhaps warrant some special attention.
This question is a good example:
Although it runs afoul of some general StackExchange "good subjective/bad subjective" guidelines, I think it could be a salvageable question. The reason it is relevant is because it does relate to a mechanical component of the vehicle, and the reason it deserves special attention is because it seeks to address the proper and safe operation of the vehicle.
While this site's primary purpose is to cover "Maintenance and Repair" issues, I would suggest that issues that relate to the safe usage of mechanical components also be on-topic. I'm sure there's nobody here who will disagree that safety should be a primary concern of any driver on the road.
I think that individuals who are experts in the mechanical functions of a vehicle's safety features would be the ones best qualified to answer questions such as these. In fact, I would almost go so far as to say it would be irresponsible of this group to ignore such questions when they can be appropriately answered here.
Additionally, consider this question which is not at all about any mechanical part - nor any part of an actual vehicle, for that matter - and yet it has received a few decent answers, no down-votes, and no close-votes:
Despite being otherwise irrelevant to the topic of this site, the question seems to have been welcomed as it is relevant to the safe operation of a motor vehicle.
EDIT: Here's another question that may fit into the category of "driving questions we may want to allow":
This question as it is now may be a little misguided (see my comment on the thread), but it does venture into the realm of what I'd like to call "preventive maintenance through good driving practices". There are some things that one can be mindful of in their day-to-day driving habits, which will help to keep their car in better shape. While perhaps not quite as significant as safety issues, I think these still have some relevance here also.
It depends: did you break something?
The background behind a situation can help in the diagnosis. The missing piece in forming a useful question is likely "what is the problem that you are trying to solve?"
Concrete driving motivated and non-rhetorical example - I have seen variants of something like this in the past:
At a track day, I experience significant brake fade after a few laps. Would stainless steel brake lines reduce the fade? Would I see shorter stopping distances?
That's a driving-motivated question with a mechanical answer.
BTW, the answers to my hypothetical questions are "in general, no and no. The brake pedal will feel better but your stopping distances will likely not change."