Sure, especially for anyone not used to writing parsers using a parser generator is a good way of validating assertions about it. But for that parser, just star

Sure, especially for anyone not used to writing parsers using a parser generator is a good way of validating assertions about it. But for that parser, just starting by cleaning it up would be a big improvement irrespective of formalism. Even if you get an unambiguous parser, if you can't read the grammar you'll end up with nasty surprises anyway...