It is quite simple, you can not leave a neg for a buyer, nor can you leave a false pos, so you dont leave any full stop,

Once you leave a false pos, the buyer can simply have the comment  removed, while retaining the green dot.  So the FB is not only against policy, regardless of anything CS have told you, but is also counter productive.

As for the  non refundable 30c,   so far I have only had it apply with a cancellation after item paid, from memory  33 cents.  Not a  big deal, and it is always possible to add the loss to the price of the  relisted item, or make it up somewhere else.