@chubbyrain said in SMIP Podcast # 88 - The "London" Mulligan in Vintage:
@smmenen I listened to the VSL analysis (good stuff, tough breaks in the games as well) and the initial part of the London Mulligan on reducing variance. I think it will actually benefit Shops and PO. A 58% chance of hitting a single restricted card without Powder is very high and both Shops and PO have powerful cards that they can mulligan to if their opener is not a typical Shops or PO opener. PO has potential access to Timetwister, Tinker, Ancestral, Tutors, Mentor, Balance, Wheel, Windfall (which could get much better), any 1 of which could eliminate the disadvantage of mulliganing. Shops has access to Trinisphere, Chalice, and to a lesser degree Thorn, Sphere, Strip Mine, and Workshop as powerful cards that can enable degenerate openings and win games with fewer cards. Dredge and Survival both benefit as Bazaar decks, though for Survival finding Bazaar is neither necessary or sufficient to win and so the rule's change won't help as much. The decks that get hit the most are the control decks that generally don't operate well on few cards. The only card that really saves them on mulligans is Ancestral. BUG Fish and Blue Aggro-Control are both going to be impacted by the new rules change.
I think you are missing the forest for the trees in the middle part of your analysis.
While it's true that Shops has a (growing) number of restricted lock parts, a Shops deck is unlikely to mulligan more aggressively (relative to other strategies) to find them, simply because modern Shops decks rely on cumulative pressure (both lock parts and damage) more than a single tactic to hold an opponent at bay, like it could do in the days of unrestricted Trinisphere.
Similarly, PO is not going to want to mulligan any more aggressively (relative to other strategies) to find the titular card. PO requires a density of mana rocks and other perms to make PO payoff. Thus, it needs a larger starting hand in general.
Your math is correct, but you are applying it in a way that does not properly account for the context in which the mulligan occurs.
What really matters is the relative rate of mulliganing in the assessment of 'who benefits?'. It's possible that all decks will be more likely to mulligan to 6 as a result of the rule change. But I think both PO and Shops (as well as Xerox) will have a lower mulligan rate increase relative to the other strategies described in the podcast.
So, if PO and Shops were to increase their mulligan rate by, say, 5% under the London rule (such as from 1 out of every 5 games to 1 out of every 4 games), then Survival and Eldrazi's will be even greater (say, 8%, from 1 out of every 4 games to 1 out of every 3), and that's accounting for any imbalance in starting levels of mulligan rates.