If I was a betting man, I’d easily put all my money on @heckflosse… 
Sounds interesting. As soon as an example series of 16 raw files is available and (more important) RT 5.9 is releases, I will give that a try… 32GB RAM in my machine should be enough for this monster files…
note that RT (and ART) already can handle 16-shot pixel shift files from the A7R4, which are not much smaller…
But for 16-shot pixel shift files from the A7R4 motion correction does not work well, because we get only 4 frames of 4 in-camera precombined raws (which are not, or not good motion corrected)
Having 16 raw frames to work with, would allow to use the motion correction algorithm in RT.
I agree – I’d actually call 16-shot A7R4 files useless for all practical purposes. But this doesn’t change the fact that they can already be handled