For God's sake don't tap your foot either. The trouble with bobbing the head is that if it is in time with the music, it emphasizes the downbeats and defeats any attempts at creating the illusion of a long phrase the spans several measures.
You wanna tell that to jazz musicians?
I wouldn't think of it as they're usually not too concerned with "creating the illusion of long phrases spanning several measures".
According to Newman it usually indicates that the player is trying to make up for a hitch in his realization of the pulse.what does he mean then??
It is like whistling in a theater, you just don't do it. People argue that any unnecessary action (a very arguable expression) should be avoided because it could interfere with your performance. Therefore you aren't allowed to tap your foot either. All these movements are reserved strictly to pop musicians and very famous pianists - the latter even becoming more famous because of their special behaviours - like Horowitz, who was known for curling his small fingers or Lang Lang for spending 50% of his energy on excitement.
And both Stevie Wonder and Ray Charles were known for their head bobbing.
It is like whistling in a theater, you just don't do it.
Unfortunately you chose a bad example to illustrate your point! Not whistling in theatres nowadays...