I really liked this article, I just have a small quibble (not so much with Gavin, but just magic in general).
When you were talking about all the things you needed: spot-removal, card-advantage, a controlling deck, you automatically went to blue. You have no bounce, no counterspells, and very little card-drawing in the deck. Yet because blue has this stranglehold over both the most efficient forms of card advantage and is considered 'the control color', you add blue. Specifically:"Against Birthing Pod decks, a control deck absolutely needs a way to shut down Birthing Pod. It looks like I'm going to be going blue-black-red—also known as Grixis—since I'm going to need blue's card advantage and selection to keep up as the game goes on. The card I want to play isGrafdigger's Cage—and since I'm blue, I can also play Trinket Mage to go find it! This allows me to fit in a small Trinket Mage package for the Pod decks. While Grafdigger's Cage does hurt things this deck is doing, it fights the Birthing Pod decks enough that it's worth the tradeoff."
Birthing pod is an ARTIFACT! You already are playing red. Doesnt red have good answers to artifacts? And as far as card advantage, why do red and black generate so little card-advantage that a control shell with those 2 colors MUST add blue? I'm asking not so much as to critique your particular deckbuilding exercise here, but more to bemoan the color wheel and general card balance in Magic cards for most of its history as a game.
I mean it's pretty "unthinkable" to try and build this deck without blue, I can see that. It would be a gimped version of what you built. But that is SAD. Black and red have the most efficient spot removal of all the colors of magic. Yet you can't reliably play them together without blue to generate card-advantage (or you can, but you in the back of your head realize the deck would just be better with some blue).
You can play a black-red aggro deck! You wouldn't feel the need to add white to generate weenie advantage, though white is supposedly the weenie color. I mean, it felt absurd to write that. I guess I'm just frustrated with the philosophy that competitive magic must have blue in it. The only time I can think of in recent memory where it wasn't involved Jund, a deck that was inherently luck-based and required less skill to pilot, and the small window when Zendikar was released before Jace rose to power.
The other colors need to have their paths to controlling decks too! Blue can obviously beat down but is REQUIRED to make a control deck. Ie- blue can do everything. Even in a deck like yours, designed without counters or bouncing, the hallmark of blue spells, you still "need" it for card-advantage sources like Snapcaster or Forbidden Alchemy (The trinket mages are cute, but you only have 3 cards to search for and 2 of them do basically the same thing, you could just play 2 cages and 2 Nihil Spellbombs, though you'd be missing out on the virtual CA of having a 2/2 body and lose access to finding Elixir).
Does stuff like this get talked about? I know we're heading into Ravnica and the other colors and guilds will make a big multicolored mess and I can't expect to not see blue being played because every color will get some play, but honestly why is this reliance on blue being the best at card-advantage still around? Flavor? History? Players quit when its not this way? /rant