I support both, though I don't support birthing pod as deeply as your list does, which might account for the difference in experience. The two decks occupy very different parts of the cube space. My pod decks are also less about ETB triggers.
Anyways, I'm never really happy with the way I describe these U/R/w aggro-control decks. Thankfully, the new U/R/W "tempo" decks in standard provide something of an idea.
You have to go to
1:22:30 in the recording, but both game 2 and game 3 show how the deck works in principle. In game 2, he has the "burn draw", where he just slams a few times with mantis rider, using it as a source of repeated damage to bring the guy into burn range and kill him. In game 3, he gets the "control draw," where he uses his burn spells as spot removal, anger of the god's comes in as a sweeper, he has counterspells, and he also has a source of card advantage that synergizes with the resource expenditure (
dig through time). The deck has a very explosive early game, but can also play a slow game.
Our decks are delver rather than mantis rider, and flashback cards rather than
dig through time or
treasure cruise; but the principle stays the same.
Also, its interesting that he opted to run
dig through time in that list rather than
treasure cruise. In that game 3, it looks like dig helped him win a little bit faster. Are three average cards in your deck better than 2 cards you know you want? And is that worth paying one extra blue for?