Legacy would mean a ban, which would be wild. The format would look very different without free counters on the offense. Thalia stock would go up too.
I like this the more I think about it. It's not just a functional reprint, there's a real choice here in terms of which card is better for different formats.
I wouldn't put too much stock in WotC's methodology unless they actually reveal it. My suspicion is there is a lot more sampling error than any of us think. Any quantitative analysis is about minimizing sources of error, and focusing solely in win% won't do that.
For one thing, you would need identical lists. Comparing archetypes is going to inject error and complexity that is pretty difficult to correct. This is the same reason why things like tracking surveys use identical questions for years and years. Changing even the phrasing can lead to different results and makes the data incomparable.
It's fine provided the results acknowledge limitations and sources of error, but people tend to like making bold statements off data that won't generalize where they want it applied. Honestly, that's where subjectivity comes into play. No one should want a truly data driven format. Subjective experience matters and is measured quite differently from win rate.
WotC should be spending time measuring things like satisfaction with a given format, whether we're talking about Vintage or Standard. They could develop a validated tracking metric and collect data weekly, bi-monthly, whatever, and measure self-report satisfaction with a given format over time. It would help them an awful lot when it comes to delivering sets that are optimized for what people want to play. Their current market research does not impress me.
This is a long winded way of saying win% is a heuristic, not a complete picture.
It hasn't been FoW or bust since Mindbreak Trap was printed. That's a reasonable combo counter. So is Flusterstorm against anything but a turn 1 kill.
If Misstep only hit instants and sorceries, it would still be good but not stupid. I don't mind seeing Misstep hit Ancestral. I really hate seeing it hit Thoughtseize, but whatever. The real damage is to creatures and 1 drop permanents that had a place in the format and no longer do. Mana dorks like Hierarch and Deathrite are practically unplayable because getting your turn 1 play tempo'd is backbreaking so often.
I really, really loathe Misstep. It's interactivity of the worst sort. At least a Chalice you can play around and remove to unlock your hand.
Also, does anyone believe that Misstep pushes people off of 1cc spells anywhere except at the margins? The format is full of 1cc spells. If you were to examine the Vintage format before the printing of Misstep and after it's printing and use, I doubt you'd find a statistical observable difference in the ratio of 1cc spells.
I think you'd see a difference in which spells. Sure, people play Pyroblast and Ancestral. They're both instants. You can sneak one through a Misstep war by fighting on the stack. I bet you'd see a large reduction in the number of 1cmc sorcery speed plays (with a possible exception of Cage, but even that might be lower than anticipated).
This is probably the main reason why Old School is a joke. Having a separate B/R list is one thing. Arbitrarily making cards work differently is another.
It's played in bars and Chaos Orb is the tie breaker. I'm not sure anyone ever claimed it was serious.
Fun as fuck, though. Fake team rivalries alone make it worth the price of a beer.