How would an optional, official parser be toxic?

[Vahlnir]

But introducing a normal parser in which you can compare yourself to others at a glance? No I'm strongly against this because my time in WoW showed me the long-term ill effects from it. The gain doesn't outweigh the negative aspects.

Yep, nailed it right on the head. Imo a parser that is used to gauge the performance of yourself as well as your party members isn't the best idea. it's one of those things that people think they want, but they don't. They should be careful what they wish for. A personal parser is fine. Beyond that I just don't see it ending well. I'm a firm believer that parsers themselves aren't bad. It's how (and when) they are used. Personal experience has shown me how much they are misused, and it is too often. Once that can of worms is opened there is no going back. People need to consider the ramifications of such a tool in the wrong hands.