This works, you know. You cast your turn 1 Aether Vial and plop down the tree at your opponent's EOT. It's butch accel. I have known of this for over a year now, and I have consciously tried to incorporate it in my new decks, but somehow I never, ever keep it in my final version. In fact, I have never even gotten it off in a game. There are some kind of design forces preventing me from using these cards in tandem, but...

I DO NOT KNOW WHAT THEY ARE!

...and it is bothering me. I just can not put my finger on it. The best case resolution to this phenomenon would be to have a wonderful deck come out of this discussion. But I would be satisfied with a strong demonstration of what it pulling me (and presumably others - I can't be the only person who thinks these two cards together are The Sauce) away from keeping the two.

Lemme start by shooting down some that I know are not responsible, or at least not solely responsible.
1. Green Sun's Zenith and Vial are a nonbo. This is true, but I have been keeping plenty of creatures anyway.
2. Arbor and Zenith push you to wanting one or two Arbors; not more. Also, not a problem. I have been playing three in several decks. In respect to the issues facing the Arbor's summoning sickness, not a problem.
3. Mana supply does not support a nonbasic monogreen land. This was an issue in one deck for sure, but not the other two or three.

All right. So here I ask you:

WTF?