Quote Originally Posted by AssertnFailure
Why would it be stronger story-telling to split them up?

An important aspect of a team is.....you know.....teamwork, and your teamwork is stronger when you keep the same group of people together for all their missions. Everyone on Gai's team knows their strengths and weaknesses, and are able to effortlessly pull off combo attacks this way (as shown with Gai's team vs Kisame several times in this ep).
It would be more realistic to split up pupils from their teacher, and send out a team of equals on an S-class mission. Yes they have worked together, but Neji is a relatively new Jounin and Tenten and Lee are still Chuunin (I think), so sending them out on an S-class mission doesn't make much sense. I don't know how busy Konoha is mission-wise, but I'd rather have a team of Gai, Kurenai, and Asuma chasing an S-class villain.

Another problem with this team is a mistake from Kishimoto: it's basically a team of taijutsu users. Where's the balance in that?

Of course, another part of people's arguments is why isn't Gai with a new team of Genins, and Neji working with other Jounin or having his own team. Like boilerph said, that would introduce too many new genins or force the writers to elaborate on other Jounins that go too far outside the manga storyline.