Across 2 characters I got like 18 burdens, but suddenly the last 2 weeks I'm getting 0.
For me the rares are just dropping coins and junk now, so I don't really bother with them that much, but Evermaw and the Pirate Ship seem to be still worth doing, and don't forget to go get your sparkly chest up in the gated area, (that contains 1 burden) you don't need the epic cloak to get in, just buy some invis potions if you haven't got stealth, and jump on a bird.
It's just RNG.
It's kind of like shutting the stable door, after the horse has bolted, but still.
while my guildie has around same coins but around 8-9 burdens
Last weeks i've been farming on my mage and haven't gotten a single one except the one i "stole" with using slowfall to the ordos sanc and opening the chest.
I did seem to be more lucky the first week then any other time thereafter. Not sure if that's don't to a nerf or whether it's just that I've not been as lucky.
I have a feeling they nerfed them somewhat overall when they nerfed the droprate from the chests at the crazy monkey..