I wonder if private members' bills are subject to the same consent. As far as I'm aware, the first time the chamber hears of these bills is when they are submitted by the member, and presumably by that stage it's public and can't be retracted without bringing a huge spotlight on this obscure rule. A private member's bill could therefore potentially be used to bring about the abolition of this practice.
If Wikipedia is to be believed, it already has been used to prevent a Private Member's Bill from being debated relatively recently in 1999: https://en.wikipedia.org/wiki/UK_parliamentary_approval_for_... Also, I don't think this rule is really any more obscure than any of the other subtle details of the UK's unwritten constitution - people who care about this sort of thing almost certainly already knew about it (I certainly did!) The Guardian is probably trying to turn it into a big scandal because they don't really like the fact that we have a monarchy.
