And What Are You Talking About With Regard To Launch Windows?
The launch window to return from Martian orbit to Earth orbit should be the same whether you are on Mars or one of its moons. You can do a short mission to Mars just like a short mission to its moons it just makes no sense given the length of time to get there and return. An orbital flybye is even stupider IMO. We did it with Apollo because we were in a race and the lander wasn't ready. We might have doen it that way anyway, but there was also the fact that the trip was short and we were not exposing the crew to a high risk for a modestly valuable test.
Regards,
Mark