This is a feature.
But what's the problem it solves?
As a bla bla ha I want to bla bla bla ha so that bla bla bal
I'm just saying the I's not clear what the problem is: Why should the branch be mentioned in the commit message - it's not (that normal) to put a branch name in a commit message. Personally I never do it - but I rarely (as in "haven't yet") seen any other developers do it either.
Let's get a description of the problem we're trying to solve, and then lets see somebody actually watch or vote for this issue, before we hit the keyboard!