I think Gayle's been a bit uneven with his bowlers, which is no real surprise given that Powell and Taylor did so well, but he didn't give Sammy a chance until this morning. Bravo ended up being the one to trouble both De Villiers and Harris, so there is good cause for a more complex bowling cycle. Those slower guys really aren't all that slow and are both very accurate.
No way in hell should they enforce the follow-on, what a waste of a 200 run lead. As I said, the rotations haven't been even and there is a lot of time left to rest them up. There's nothing wrong with the batsmen getting a bit more time in the middle in the first match, either and a solid follow-up innings would send them euphoric into the next stage. Plus, they would do well to be wary of South Africa, not only do they have enough quality to come back into the game, but that scenario also leaves them batting last against a decent spinner.