Nowadays the same workflow is doable using opensource tools like Git and GitHub for anyone. Here's how the process works:
- request a change to the system
- do the changes
- integrate them to the so called main line
Using GitHub it's dead simple:
- file an issue
- clone the repository, do some changes, check them in
- put out a pull request for the maintainer to integrate your changes
All that takes some 2-3 minutes if you know what you're doing and if the test suite you're dealing with is fast enough. Piece of cake.
Now if you'd like know how it looks like using Rational tools (and I mean the good stuff, fully integrated) take a look at the following screen cast.
I hope ClearCase will soon be seen for what it really is: a performance and evolution blocker.