The why is that it is irrelevant to my claim.
Except it's not irrelevant since you're obviously introducing new variables without specifying them (and since you didn't link your sims then I can't try to figure out what I changed). This entire time we've been discussing 36 (+12 strength) or 30 (+0 strength) AB for DW. So if you have 34 AB then...what did you change?
If, for example, you dropped the BAB by 6 and added in EWF/EP then you're losing the lowest attack, which can be significant.
Now that you actually have linked the sims, I can tell that you were looking at +8 strength and +10 strength which is perfectly valid, but you might have changed something that drastically skewed the results.
You can compare scythe and kukri all you want, just don't quote me as being in opposition to your claim as I have not made a claim concerning scythe that you would refute.
The double weapons have always been the issue of the comparison, with the claim that on low magic they can overtake their corresponding 2-hand counterparts. They will never overtake the scythe, so I never discussed what was the best weapon, merely what weapons were overtaken by what.
If you're going to talk about DW kukris (and you specifically mentioned kukris) then comparing it to the scythe seems perfectly valid.
And the 2H counterpart of the double weapons IS the scythe -- all exotic weapons. We can compare the double axe to the greataxe and double sword to the greatsword if you want...but if you're picking up exotic weapon proficiency and are on a level 40 server then you're picking the scythe for 2H.
I'll refer to those as 1, 2, 3, and 4 respectively.
On 1, we see that at 32 AC DW and 2H are virtually identical, with 2H being slightly better on average. And 32 AC is BELOW the "weak" threshold that you defined by 2 AC. And as of 36 AC the 2H is always equal or better.
On 2, same story, except the 32 AC threshold becomes 33 AC and 2H is always better or equal for 37 AC.
On 3, same as 1.
On 4, same as 2.
So those graphs indicate that even for the weak mobs you mention, 2H is doing just as well (without needing to sink three extra feats in for DW and without a feat for exotic (so four feats saved total) and without needing 15 dex) as DW. And as the mob AC increases the 2H goes from potentially being marginally behind to being marginally ahead.
All that extra investment for a virtually identical (and slightly worse for relevant enemies) result is hardly being competitive -- and this is also always assuming the character will have EWS.