I failed on my first attempt on the new striking dummy

[Waliel]

It's not a rough estimate. It's pure math and is a more reliable number than what a parse will give you. Because parsers estimate dot damage.

If a dummy has 200k HP and you kill it in 150 seconds then your dps is 1333. That's not an estimate, it is factual. You just can't be super precise since we don't have tenths of a second.

So a random site using math is somehow more accurate than a parser that uses math? Got it.

Parsers have been very accurate for a long time. I did BLM A5S in i210 and completed it in roughly 2:55. Using that site puts me at 1558.86 while my parser gave me 1557.17. I'd call a 0.1% difference to your factual math pretty precise.