I don't think your post really responds to my questions. I am going to go out on a limb and assume there is a language barrier, as it appears English may not be your first language. In which case you may have misunderstood my questions, or I may be misunderstanding your response.
The first point, I said "This suggests that someone would only want to improve themselves while doing hard content. This also suggests that "hard" content is the same thing for everyone, which it clearly isn't."
This was in response to you suggesting that the tool is only useful in hard content and to be put in PF and left out of DF. To reiterate, the tool is not only useful for hard content, and hard content is subjective. For example, someone new to to the game may want to be testing themselves and improving in Brayflox normal mode.
The 2nd question was in regards to your statement that 40% of MMO's have a parser. I was just wondering where that data came from? Was there a study, or is there a list somewhere? Is this just your experience from 3-5 MMO's you've played, or maybe from your experience playing 20 MMO's? To put this in perspective, on mmorpg.com's game list, there are 865 entries (yes this includes some unreleased titles).
EDIT: In regards to your overall message, that is great. It would be great to come to some sort of consensus and/or compromise. My issue, is that I see more issues arising from meeting half-way. Giving partial and not full information may lead to people having the frustrations that people expect with a parser, but will lack the information needed to provide credibility and/or to confirm their suspicions. That's why I think a personal parser will be more harmful than a public one. I also think that having it in some situations and not all would be annoying, and likely result in similar issues as above.
TLDR Add it full or don't add it, because something in between will just cause issues.