I don't want to be overly pessimistic here, but it seems like at this point the best-case scenario is "too little, too late." Windfall/Mind's Desire/Tolarian Academy/Time Spiral/Timetwister/Time Walk/Thirst for Knowledge/Force of Will/Mana Drain/Counterspell/Intuition/Ancestral Recall/Dream Halls/Mind over Matter/Morphling/Ophidian/Hurkyl's Recall/Brain Freeze/High Tide/Frantic Search/Brainstorm/Cloud of Faeries/Palinchron/Donate/Curiosity/Fact or Fiction/Parallax Tide/Braingeyser/Stroke of Genius/Mana Short/Treachery/Opposition/Old Man of the Sea/Boomerang/
Snowfall/Accumulated Knowledge/Memory Lapse/Mana Leak/Force Spike/Daze/Forbid/Prosperity/Impulse/Stifle/Tradewind Rider/Standstill/Arcane Laboratory/Back to Basics/Tinker/Gush/Misdirection/Spiketail Hatchling/Cowardice/Upheaval/Deep Analysis/Future Sight/Fabricate/Thoughtcast/Trinket Mage/etc./etc./etc. have already been printed.
There is an absurd amount of cards that have contributed to blue's being the best color in multiple formats, sometimes by itself and sometimes in combination with any number of the other colors, over the years. All of these cards are not going to just go away. Saying, "we won't do it anymore" isn't going to fix anything--not that I'm suggesting an alternative solution. I don't think there is a satisfactory solution to this, especially not in the short term.
Rosewater's article came across as, "Blue has been too good. We are going to stop making blue the strongest color in future sets. I mean, look at how good blue is. Wow, blue has really been way too powerful. Don't believe me? Here, look at these statistics..."
EVERYONE who has been playing Magic for any significant length of time KNOWS how good blue is and even casual players generally have a vague idea of how well it has done in tournaments. An article to tell us this is entirely unnecessary. If they want to announce that R&D plans on weakening blue in future sets, that's fine, but maybe the information in an article should be more...informative. Like, "There are some really weird reasons for not having begun this process earlier. Obviously it is too late to start earlier, but I can assure you that we will be doing it now..."
Yeah, blue has more restricted cards than the other colors. Yes, blue has been made ridiculously versatile. Oh, and of course blue has been the most powerful color in recent blocks (which couldn't possibly be a direct result of blue getting the best cards in virtually every set for however long now). Blue has tremendous capacity for card advantage in comparison to the other colors? Really? I mean, I couldn't have learned that by playing the game. I only realized it after Mark Rosewater pointed it out...