I use the 3-way-colour correction in videos in two ways:
1) Correct Colour:
If white balance was not made or light situation has changes after WB, a video can have a colour cast. I correct by adding the opposite colour in high (light colours).
Example:If a white wall is a little yellow, I add a colour between blue and red (opposite colour in colour scheme).
I use it to bring mood into the video. To make a snow scene cool I add cyan to the video, to make a lovers scene more warm I add red or orange. In a summer landscape I would add yellow or green.
An interesting effect can be to add different colours in low, mid and high.
Add blue to low, orange to mid and yellow to high.