My standard way to think about stuff like that is to extrapolate to infinity: even if your tail wind were infinite and you’d arrive in 0 time, your way back wou

My standard way to think about stuff like that is to extrapolate to infinity: even if your tail wind were infinite and you’d arrive in 0 time, your way back would have infinite headwind and you’d never make it back. Conclusion: increased wind increases the round trip time.