You do know that doing an edit to an existing post within the seven day window creates a relatively hefty blockchain transaction every time you do it, right? And every time that you do it, a client reading posts on the blockchain is required to go through all of the blocks which have been committed since the original post creation time looking for update transactions so that it can have an actual coherent view of a post to present to a reader.

Editing posts is one of the worst things that you can do if your interest is to keep the number of transactions and amount of data and which is needed to be transferred by the witness servers low. They hit hard not just when they change their committed, but for ever after whenever that post is read.