"Are you walking or driving?"
Translation:A bheil thu a' coiseachd no a' dràibheadh?
draibheadh, -idh nm (or dràibheadh) vn of draibh driving
AFB only gives the forms without the stràc. But he also gives the pronunciation as /draiv/. Crucially there is no length mark in that so it is a short diphthong. Dwelly does not give the word, or any similar word for 'driving' or 'droving'. So the dictionaries are strongly preferring the version without the stràc.
Next we look at the phonology. The stràc makes the diphthong longer, but I do not hear a long diphthong - it is as short as I can reasonably make it. Of course I have a personal interest, as you will see from my name, which is much the same without the r. I spell it without the stràc. Some people spell it with. People can spell their own name how they like. But I decide how to spell my name. I do not appreciate it when people tell me how to spell my own name. And the diphthong in my name is short too. So there is no stràc on it.
So, overall, the version without the stràc is preferred by the dictionaries and phonologically correct, but the stràc version is accepted as an alternative.