There is quite a bit of leeway when you have real world data. You have to clean it. You can always find some justification. This is not neatly black/white at all. Similar in all other fields from accounting to law. I think it's a serious issue that we managed to make so many people believe way too strongly in absolutes ("science" as a magic word to end all discussions, because hey, "science" and "data" - now we have an objective reality!), when in reality the world is way more messy.
The original parent comment is describing someone hand-picking samples to obtain a predetermined conclusion. I know touching data to clean it before analysis can be a grey area, but the original parent comment -- if it is accurate -- is describing clear-cut fraud.
I refer back to what I wrote. You miss the point. There is no black/white in what is necessary and unnecessary or even nefarious "data cleaning". You just use the same fuzzy undefinable words again, but you did not make it any more a "hard fact" than any of it was before.
