I still think saying "No political parties" conveys false impressions about it being possible to "ban" political parties, which is impossible. I think saying "No political parties" carries this impression even if you don't intend it to. What TDG, and any government, can do to discourage (not really ban) political parties is to prevent any party names from being printed on official government anything and more importantly no political parties listed on ballots. Banning political parties mostly is a social norms peer pressure thing, not a government ban.