@coriolissystems iPartition makes partition management on OS X a happy dream.
It does only what you expect.
If you have worked with OS X’s Disk Utility enough you know how unpredictable it can be. I don’t know why it is that way, but you do have to be careful and thoughtful even if you are in iPartition. I suppose that it has to do with the OS and neither of the tools.
I just know that iPartition makes it trivially easy to resize and recreate partitions and on OS X 10.11 it is impossible to do so with Disk Utility!