Hi Strytus,
I'm familiar with this situation. The quick workaround involves copying the blendshapes that you need to adjust to use them as the base model for the adjustments that you will make on the active blendshapes. What you do it take the problem blendshapes to their extreme positions. Then, you template the copied "correct" version and adjust the distorted version to meet up with the correct copy and reposition the verticies. Of course, I work in the orthographic views and wireframe. Doing it that way keeps you from having to delete the blendshapes. Good luck my friend! see ya soon.