KanecoThat was actually what I had done originally, like here in this video, but all the test renders I made and also this final render it seemed the effect for some reason got fucked in the process and it only caught half clip. Something is wrong with the blur plugin so I just decided to remove it alltogether, but I rendered again mainly because of the render issue at 4:12 that I noticed yesterday after uploading.
What I would do is actually re-record that demo with mat_motion_blur_enabled 1 set, and with an absurd intensity level. Then I would just fade between them.