I am still at a point where I have to focus on the knitting, so right now the most I can do while knitting is listening to music that I need to learn, or participating in a conversation that does not take 100% of my brainpower.
EDIT: Revelation. I can also play idle/incremental games while knitting.
If I’m doing an easy pattern like in the round I can get away with watching TV. Otherwise it’s got to be just reruns that I can zone out a bit.