I don't think that would be helpful, haar cascades have too many false-negatives (in part because it relies too heavily on specular reflections from your face's

I don't think that would be helpful, haar cascades have too many false-negatives (in part because it relies too heavily on specular reflections from your face's T-zone). Probably worth just using the CNN, you can make something else do region proposals if you really want. Probably another net :)