Avo must have some sugars in it, and some starch that can be converted through the mash. According to that video the main effects are a bitterness (I get that, especially if they threw the skins in) and creaminess. (I would have thought all the avo fat would have just sunk to the bottom).
Hey, sounds like it's a bit of a hit anyway. I won't be brewing with it soon, there are plenty of other plants and herbs and fruit to brew with first!
I watched this on the ABC the other day. Not sure if its mentioned in the online video (can't watch it where I am at the moment) but yeah, the main problem is head retention. The head dissipates to nothing immediately.