Wizards R&D, in its announcement, offers the following summary of what is motivating the change:

As the rest of the format has caught up in power level, these two cards have been on R&D’s short list of cards to reexamine for unbanning. We’ve been closely monitoring the evolution of the format over the last several years and chosen this as the best time to make a change. This is the right time for several reasons:

  • Modern’s return to the Pro Tour, shining a spotlight on the format, makes this a great time to revisit past decisions and see if they still make sense in the current era.
  • The data we gathered both from the Pro Tour itself and from the several weeks of Magic Online play as pro players tested for the event have helped us cross-check our decisions against what’s doing well in the real world.
  • Compared to other B&R windows, this one has the maximum amount of time before another Modern Pro Tour. This will allow the format to breathe and evolve without immediately undergoing the pressures of the world’s top competition.
  • The reprint of Jace in Masters 25 will provide greater availability for our player base.

I’m not sure I can draw a straight line from these observations to a sustainable, scalable model for when to unban powerful cards. Let me post it again and provide my commentary below each section.

As the rest of the format has caught up in power level, these two cards have been on R&D’s short list of cards to reexamine for unbanning. We’ve been closely monitoring the evolution of the format over the last several years and chosen this as the best time to make a change. This is the right time for several reasons:

The rest of the format is indeed doing powerful things, but what does it mean to “catch up to,” for example, aggro-control with Jace, the Mind Sculptor near the top of the curve, and Jund with Bloodbraid Elf near the top of its curve, if those decks aren’t in the ecosystem? All right, if we’re being charitable, then “catch up” means that Jund is just an okay midrange deck right now, the other decks don’t fear it in the way it was feared at the outset of the format. Fine, but that’s pretty far from a proof that reintroducing scary tool X won’t change that. So let’s get the “reasons” section.

  • Modern’s return to the Pro Tour, shining a spotlight on the format, makes this a great time to revisit past decisions and see if they still make sense in the current era.

People invest in the PT as a way to see what’s going on in Modern in this moment in time. B&R changes shorten “this moment in time” to basically nothing. Next Modern PT, the chatter about what will be banned or unbanned right afterward will be deafening.  This chatter never goes away, but this cranks the volume up. Don’t get me wrong, there is no perfect time to announce changes. I guess this one makes sense, certainly more sense than right before the PT.

  • The data we gathered both from the Pro Tour itself and from the several weeks of Magic Online play as pro players tested for the event have helped us cross-check our decisions against what’s doing well in the real world.

What’s going on in the real world is a healthy and fun. But there’s not much data there about whether Jace, the Mind Sculptor will change that.

  • Compared to other B&R windows, this one has the maximum amount of time before another Modern Pro Tour. This will allow the format to breathe and evolve without immediately undergoing the pressures of the world’s top competition.

Wizards R&D is in the middle of a passionate love affair with hiding data in an attempt to keep things healthy and organic longer. They announced more MTGO deck list revelation changes, and here they cite keeping the pros’ optimizing hands off of the cards longer as a feature rather than a bug even though all the pros do is accelerate the pace at which learning happens. I guess once you’re in the headspace of “shaking things up” then this makes some sense, I’m just struggling to put myself there I guess.

  • The reprint of Jace in Masters 25 will provide greater availability for our player base.

Ah, they buried the lede. We’re not just changing the weather—we’re selling umbrellas.

Their explanation that follows the timing justifications mostly make sense. But they make sense in explaining why there is upside potential. But not in why that upside potential is commensurate with the risk. The risks with Jace, for example, are that all the cool things people are doing with Snapcaster Mage converge onto a small handful of ways to best utilize both Snapcaster and Jace.

And what if it is the case that Tron was good against Snapcaster plus Disdainful Stroke and Ceremonious Rejection precisely because the blue deck didn’t have a card like Jace in the midgame, and Thought-Knot Seer was worth the steep investment for similar reasons (and the fact that bouncing it at very low cost was difficult, not easy), and a million other little equilibria for which the Pro Tour provided no data are at risk of being disrupted? I guess it all does come back to “If it Ain’t Broke.”

Lastly, many of us, myself included, did not miss Jace, the Mind Sculptor because we have had enough of the Jace, the Mind Sculptor subgame for an entire lifetime. The subgame where your opponent finds a fetchland nearly every turn and thus has to shuffle. The subgame where your opponent uses “Brainstorm” nearly every turn, which is a cheater’s dream of cards being swapped between sensitive and hidden zones. The subgame where everything else stops on a dime because your opponent was brave enough to spend 4 mana on one card. I need this back in my life like I need to hear “Mambo No. 5,” “The Macarena,” and “Call Me Maybe” just a few thousand more times.

“Playing the Billboard Hot 100 has been working well; it’s got a diverse range of styles and something for everyone. Looking at that data, we at I Heart Radio believe the conditions are right to re-introduce ‘Who Let the Dogs Out’ into heavy rotation. We do not believe this will necessarily cause people to quit listening to the radio or that we will need to ban the song permanently after this.”

“Okay… But can’t we just, like, not do that?”

Happy Brainstorming everyone.