Sorry Yugl but BA merits are only good if you want to make epeen SS of Everyone's grudge with set bonus proc but maybe even not because you are limited to 10min convergence timer
BA merits for cleaving are useless, even more for average player who 2-3 shot mobs instead of 1-2 shot ( ie: whirl -> dream -> BA charged -> dream -> thermal instead of whirl -> ba charged ) because of lacking best equip. I have never pulled mobs fast enough to not have BA up in a moment I need it. Even if you one shot you need to buff yourself then pull then sleep them and unless you pull 4-5 mobs it is just impossible.
Furthermore even if you for example doesn't pull yourself but have a puller and you only killing ( tho really mob respawns after 30+ sec so you would need to pull 2 families to gather them before BA is up) it's not really that hard to use one more spell to kill them then w/o BA. It's not like you will have another group of mobs waiting for you if you kill them 10 sec longer.
As for physical merits. I don't really know why you even need proofs? If you using an Almace you want to use att food not lol acc and in this case on mobs like dragua, Orthurs etc. where I was near acc cap when swinging I definitely wasn't on blue magic and I cast in af3+2 head and i have 5/5 physical potency.
1000 needles is not really good argument since in 5 days it wont exist anymore.