Well, if you deeply understand the code and reasons behind it (or it's superbly documented esp. with tests), the tool does not bring much beyond being a convenient backup or checkpoint system.
And especially if you don't have to work with a team.
I feel that a free and open tool that allows you travel through the 4th and 5th dimensions with your code is very useful, especially when everyone tends to forget what they've written several months ago. It's also a tool that forces you to document your changes.
Is it possible to climb a mountain without equipment? Sure, but it's a lot more dangerous and it'll take you longer to reach your goal.
And especially if you don't have to work with a team.