How does SE justify these ten min enrages, but doesnt let anyone know their dps

[Reynhart]

So ur telling me when u start to see 100k damage 80 k damage as opposed to where u started seeing that improvement means nothing

You have it completely backwards. So, you're doing 10k damage, then what ? Again, no parser will tell you why you did such low damage.

What the game already offers, however, is training dummies tailored to a specific ilvl. So, you go to the corresponding dummy, and you realize that you can't kill it. There, it tells you the same information that a parser does : You're not doing enough damage.

With that information, you look at guides, seek advice, and improve yourself, without ever needing an actual damage number. And when you go back to the dummy, you now realize that, first, you can kill it, and second, that you have a fair amount of time remaining. That sure means something, but again, you don't need a parser for that.