@fsecco Thanks for your helpful commentary. I do appreciate it. I didn't really intend to get into a discussion about specific SB cards, but it appears we have one, so I'll just say this: I don't have any particular intention of playing Jailer or Linvala myself. I mentioned them only because they had already been brought up by others in this thread. Similarly, I may or may not actually find Council's Judgment worth playing. In fact, I have not yet played White Eldrazi at all. Since I have had opportunities to play 100% proxies, though, I have wanted to change things up and play a number of different decks. You are probably right that I would be better off simply racing Merfolk with an Eldrazi deck. I haven't tried it yet, but I'm more than willing to take some advice.
So, to return to the original topic, it looks like your summary would boil down to "don't do that" with respect to using xWW cards. "Pick a different strategy." The mana base just can't handle double white. It looks like @Stuart is pretty much on board with that too.
I can live with that. In fact, overall, it looks like it may be the best way to proceed.
Does anyone else draw different conclusions? What experience can anyone offer that would support or reject xWW? I'm not yet committed to a course of action. I'm really interested to learn from anyone who can tell me anything useful.