Maybe he is saying by removing trusted root certificates he will trade the possibility of receiving a fraudulent certificate the first time he uses a site for the possibility of not being warned if a certificate changes because the trusted roots are compromised. If he needs to worry about state actors there is an argument to be made for this trade-off, but really if he was worried about that he would be delivering certificates out of band and not visiting any unknown websites on the machine he needed that level of security on. (Maybe justifiable against mass surveillance where you're a general target rather than a specific one).