REB737, it still depends on local instructions. When there's no cat2/3 ILS, then it's all about ensuring that the runway is clear from other traffic and obstacles and that any risk of collision with other traffic on taxiways is reduced to minimum. For example, at my aerodrome, there can be only one aircraft taxiing at once, and additionally another one pushing back, provided that he's well clear of the taxi route. Taxiing is permitted only behind follow-me car and the duty officer checks the entire runway for obstacles before each departure. And there's no other vehicle traffic permitted.