Perdu Weapons And There Latents

Wiki shows for most/all of the Perdu weapon class there being a latent effect of ACC+5 and Att+xx (different for each weapon. Now it is super simple to see how they give +xx Att when latent activated BUT how does one say it has ACC+5. From my understanding on ACC there is a general cap to mob ratio. But even there is no 100% solid way of saying something has +acc hidden effect (as far as i know). Will someone please fill me in on how this was determined and how this has been proven without a doubt (any doubt = not fact = shouldnt be posted as a stat)

Thx in advance

Its called 'Word of God'.

Frequently, a book gets published in Japan with all sorts of crazy info squeezed out of SE.

Same way we know Y's Scythe has the same hidden effects as a Dark Staff.

Also, accuracy is easy. The math is simple to know your exact accuracy value, and the 'bounds' of high evasion and low evasion, you can find the amount needed to make a mob go from no check to 'low evasion', take off five accuracy elsewhere and put the Perdu weapon on, and see it go 'low evasion' again.

Find something that checks high evasion, add accuracy until it says it doesnt have high evasion. Subtract 5 accuracy so it now says high evasion again. Equip perdu weapon.

EDIT:
Let me make this a little more correct.

If you are testing something like Perdu Volge, equip a different great axe and do the above. Then swap back to the Perdu. If it no longer checks High Evasion then you know you have accuracy. You can find items that add or subtract different amounts of accuracy to pinpoint how much it gives.

P.S. Facts can be doubted. It doesn't mean they aren't facts.

I wasn't reffering to a fact being doubted but that it was doubted to be fact.

Honestly i was not aware that increasing/decreasing Acc would change the evasion con of the mob. I can clearly see how they came up with the Acc+ bonus these items.

Thank You for the information.