We were a bit surprised to find that TL4’s can add “Staff notices”. Since TL4 are not considered Staff, is this intended?
Obviously TL4 are manually assigned and there’s some trust involved. But this notices even appear identified with the moderator shield next to them. Trusting TL4 to help run the forum is different from having them speaking for the forum Staff?
I find them quite useful as. TL4 on another site I’m on, though I obviously stick within the guidelines set out by the moderator. 
As you have manually promoted these trusted users to TL4, could you also simply set some guidelines as to when would be an appropriate time to use them?
I think you can keep an eye on the activity in your staff logs by filtering for ‘add staff note’, if that helps?