Have each boss in WoD drop 2 chests per party.

[Eidolon]

There's less gear in WoD than there is in Coil; not sure if it is half as much, but it's close.

One chest per party per boss makes sense when the loot pool is about half as big.

There's a single boss in each TURN of coil. Thus, you cna choose what you want to farm and easily blitz it down. There's no such choice in WoD - it's all or nothing.

The difference is in completion time. I don't know any coil turns that could take more than 30min on a one-shot. Meanwhile WoD will likeley take -at least- 30 minutes, most likely 45-1 hour. It's quite the time commitment if you want only one specific drop.

Edit-in: Though you're right, there is slightly more gear with Coil. Not much. Enough to cover Healing, Slaying, Aiming, Fending, and Casting (5) accessories * each 4 = 20 accessories. It's a little bit of a wider pool, to be sure.