I have seen many masters taking notes while playing chess.
What rule forbid taking notes

Note taking should be personal. This rule is strange. Since what he is writing is not offensive or insulting in any way.

He was writing self-motivational notes, double and triple check moves something of the nature. Quite childish and strange, but harsh to be forfeited. Technically, if have particularly anal arbiter, can be forfeited if write down moves before they are played with current rules. Think the spirit of the rules is to disallow turning up with written opening preparation, which is obviously cheating.
I can't get, how was So forfeited for taking notes. Was the note distracting to his opponent or what. If the face of my opponent is distracting can he be forfeited?