So happy to see a post on this subject. One of my biggest pet peeves is carelessly written UI copy and microcopy and the challenge we face to instill a sense of urgency in this area amongst different stakeholders - from the dev team to senior management.

Not only do we need a solid professional to own this (and follow the kind of best practices you advocate) but also a champion to drill this down in the design process, so no evaluation, testing and review of user experience ever happens with "lorem ipsum" in it!