I figured I would contribute here even though this is not my video
This is serious shit IMO if you really practice this a lot. Just try it once
wait until you get to using the pinky and ring finger during this exercise to feel how much this will benefit you.
I have been slacking but I do this a lot and used to do the quick version every time I touched my guitar. Really really helps IMO.
Start the video at 9:00 for the specific warm up. Is a bit lengthy but worth it.