1. airport has // runways. The longer one has been designated for landing and the duty takeoff runway is the shorter, but adequate one. The first runway to arrive at is the duty takeoff runway. There is no landing traffic. You are in sequence for takeoff. Which do you use?
2. airport, for local reasons, is using one runway direction. The wind shifts and results in 8kts tail wind. You have performance for 10kts. What do you do? Use the duty runway or request the reciprocal with the incurring delay?
Safety: a good concept. Remember the days before 2 engine ETOPS. Shock horror. Why would you do this when there are 3 & 4 engine a/c around. Then 90mins ETOPS, then 120, now 180. Not saying it's comfortable, but......once you leave the 60 mins your senses become very alert; like the first time I crossed open water in a single piston. OMG, the engine would quit as soon as I left gliding distance.
But here we are, possibly the end of B747 in sight and the world reverts to twins everywhere. Are guys requesting non-ETOPS routes or flying the 180mins routes? Similar philosophy. You can take the argument of safety to any length and decide to stay in bed.