As a fallout from work on Pentax Pixel Shift, RT dev version supports raw files with more than one frame.
Means one can also extract both frames of Canon EOS 5D Mark IV dual pixel raw files in RT.
The files contain one frame which is a+b and another one which is only b. That means it would be at least possible to recover clipped highlights which are clipped in a+b but not in b. Doing that on raw level would be better than in post processing. So, if someone here uses a Canon EOS 5D Mark IV and RT, please let me know