We pretty well mastered that technique back in the Gemini program. One possible concern about splitting the mission like that is what happens if the crew has to abort on the way to Mars? If the consumables for the return trip are in Martian orbit, they'd get pretty hungry before making it home. If they have enough consumables to make it home during an abort, then what did they gain by splitting the mission? One other thing - space vehicles frequently break. Just because something is in orbit around Mars, there's nothing to stop systems from malfunctioning. I saw that often enough when doing satellite operations.

There are several variations on what you're proposing. One that has received a fair amount of attention is Buzz Aldrin's Mars Cycler concept.

While I'm not optimistic about seeing a manned Mars mission in my lifetime, I suspect it'll probably be some variation of a Mars Orbit Rendevous scheme similar to Apollo.