I have little doubt it could be written, but at risk of going blue in the face, this was irrelevant to the original question ("what do you dislike about this syntax?"). Never mind, 'truth' has won out in the end regardless, and I note for future that the presence of Lisp on a CV is fair reason to pause and reconsider.
"My first thought is how I'd parse, modify and write it back without losing user's comments, formatting, changes and suchlike. Is this some well understood format with libraries for common programming languages?"
