I'm currently in the process of writing an application for a PhD scholarship at a British university. The school's system requires a CV (resumé) with attached cover letter, along with a few other documents.
My intended supervisor is someone I've already worked with for my MSc thesis, and he has said that he's willing to proof read and suggest changes for my cover letter, using his knowledge of the university's system and what the interview panels are generally looking for to help word it in such a way to tick the boxes that he anticipates the selection panel will be looking for.
He hasn't shown my cover letter to anyone who will actually be involved in the selection process, and he himself will not be involved in the process in any way, but a part of me is still concerned that such help might be giving me an unfair advantage over other applicants who don't have the same kind of relationship with their prospective supervisor. Is receiving this kind of help OK or not?