Feature request: the ability to create multiple pull requests for the same branch (without merging)

Ideally it would be nice if the BitBucket workflow supported...

1. Developer writes a block of code.
2. Developer pushes commits to BitBucket
3. Developer creates pull request (for the code to be reviewed & approved)
4. Developer continues writing code for the same branch.
5. Developer pushes commits to BitBucket
6. Developer creates pull request (for the code to be reviewed & approved)
7. Developer continues writing code for the same branch.

The advantage here:

1. code reviews can be performed using a Pull Request on a regular basis
   (A) thus allowing problems to be caught earlier in the development process
   (B) thus making it easier to perform the code review (i.e. looking at 100 lines of code versus 1000)
2. the master branch is not updated until the feature is complete
   (A) as a result, the code base is more likely to remain stable

Is there a way to accomplish this without...

1. constantly pushing to master, or
2. creating yet another branch?