Yes, definitely. If this was anything like my own experience writing parsers both the wrong way and the right way, the original programmer probably could have saved time by going out and reading a couple of textbook chapters, doing the homework problems, and reading the Bison or ANTLR manuals, and then doing it properly. Implementing a parser without knowing what you're doing is not quick or easy.
Worse than that, it is a frustrating, Sisyphean endeavor, always taking one step forward and two steps back once you get past a certain point. It is not a task I'd wish on anyone. It's a lot like writing a multithreaded program when you don't have a clue; you get a few quick things working and then descend into an endless hell of fixing one bug and causing two others, forever.
