Becoming a better player
Knowing what your opponent is on is HUGE....in certain matches. If you are on blue and you are facing shops and know it, what are you going to do? Are you going to mulligan into your single hurkylls? Are you going to mull until you have 3 basic/fetch lands? if you do, you likely lose on mulls more than you win on luck-sacking into the perfect hand. Your best bet is to play that deck you are comfortable with, hope to make smart plays and minimize error, and win with any luck.
Now if you are on a certain deck running 1-strip/4-waste and perhaps even something like main sorcerous spyglass and KNOW your opponent is on dredge, you are damn straight mulling a good hand of 7 for a decent hand of 6 with waste/spyglass is a HUGE gain in game 1. It is the difference between a near auto-loss into a favorable g1 matchup. Even in a deck you are semi-comfortable with as opposed to a deck you've mastered, if you have ample cards against a deck that hinges on one axis and know you are facing that deck, you are much better off. The same could be said running a null rod-based deck vs PO storm. If you know that matchup is happening, you are better off mulling into the 1-of chalice or turn 1 rod off a mox than keeping a solid hand that won't win until turn 3 or stop artifacts.
If you have 3 basic land + an orchard, and an oath...you keep that vs shops. If you have that hand vs PO, you probably lose. If you have that same hand in your oath deck and also know you have FoWs and null rods, you probably mull that away instead of hoping to live to turn 3 with no answer to getting stormed out.
So, the answer to the question again is: it depends. Based on the matchup, the knowledge vs mastery can make a big difference.
People have known what I was on for the last 5+ years and that hasn’t stopped me from succeeding. I don’t disagree that it can win you matches, but mastery is more likely to win you tournaments.
@will I assume you are a dredge player? I think one thing that limits the effect of knowledge parlaying into a win is that most players rely on their SB completely to beat things like dredge. If you happen to know the opponent is on dredge AND have ample maindeck answers, the knowledge can prevent you from having to win games two AND three and set you up to win game two OR three (since g1 vs dredge is a loss for many people). If you have the knowledge, but no maindeck answers, you don't get to use that knowledge to your advantage.
Again, assuming you've been on dredge the past 5 years...if your opponents played a typical 60 with very little dredge answers main, then having them know what deck you are on would have minimal effect vs you. All they would "know" is that they're going to have to win games two and three.
I’m a Workshop pilot.
@will Then yeah - I already mentioned shops. Knowing you are on shops doesn't benefit a blue player...what are they going to mull into that would cripple you? Knowledge vs mastery is only applicable when facing a deck the hinges on one axis - like bazaar for dredge or artifact mana for PO storm. And that's also if you maindeck ways to hit bazaar or shut down artifacts (waste/rod). If you are facing blue, fish, or workshops, there's literally no maindeck card you'd want to mull a good hand away to find.
The gains of knowing your opponent's deck is limited to certain decks - namely dredge, PO...maybe oath if you maindeck something like cage/priest/decay or are on the mirror and want a hand of orchards as opposed to oath. Decks like workshop (aggro or prison) blue control, big blue, most fish builds are immune to your opponent knowing your deck because there's nothing they'd prefer to see over a good opening 7 against you.
@thewhitedragon69 your opponent won the die roll and choses to begin.
You draw a 7 of :Mental Misstep, Flusterstorm, Mox Ruby, Mox Sapphire, Preordain, Dack Fayden, Treasure Cruise. Its a fine hand in most cases i would say.
But if you know your opponent is on shops, this hand just loses immediatly to any turn 1 taxing effect. You should mulligan this hand if you kbow your opponent is on shops, making the shops deck (and pretty much every deck out there) not immune to knowing the matchup.
Sure, knowing what your opponent is on benefits you sometimes more or less, dependent on the deck, but its never absolutely irrelevant.
Still, really mastering a deck and knowing all the fine lines, instead of constantly switching just to suprise your opponents, but playing them all mediocre seems the way more solid approach.
Playing a spread of decks medium well is a recipe for failure. Being varied is good, but you can achieve the same effect off actually being varied by throwing a curveball every so often. I'm primarily a blue pilot, but I've shown up to events playing Shops or Dredge on occasion, so people know that I could be on other decks.
Even from those limited experiences, I will attest that playing poorly loses a lot more games than having opponents mull some marginal hands against you.
To be clear, when I said:
mechanical playskill > mental hygeine > decklist > inducing your opponent to make mistakes > information management
I didn't mean that information management is irrelevant ... I just meant for most players, there are so many more important things to worry about that concentrating on hiding your deck is a wasted opportunity cost.
Can you get a few % points by an opponent misplaying because they think you're on a different deck? Sure. But all of those %'s go away if your opponent scouted the room. They go away in the top 8 when everyone knows SOMEBODY who has played against you in the swiss. They go away when your opponent isn't a regular and can't guess what you're on even if you always play the same deck. Most importantly, they go away in game 2, which is > 50% of the games you're going to play.
Nobody here is making so few mistakes that they'd get more mileage out of that .05% bump in 10% of games, rather than just playing the deck you don't make game-ending mistakes with. For certain, I don't come close to playing that well. I'm not the best player in this thread, but nobody here is playing at a zero-mistake level.
Does this mean you should never switch decks? Not at all. But there are other more important factors. Playing a matchup from the other side of the table can give you real insights on how to win, and if you're similarly strong with two decks, it can be correct to play something different as the metagame changes. I just don't think surprise value has a lot of weight here.
If you run into a situation where getting an information advantage is free? Awesome, go for it. ... but don't sacrifice something more important to get it ... and almost everything in magic, (like avoiding play mistakes or adapting to the local metage) is more important. Don't pitch your Ancestral to counter their Preordain.
@aelien "immune" was perhaps not the right word, but "far-less-impacted" is more apt. As I said, knowledge of the opposing deck in shops vs blue is really minimal advantage. This is very different from knowing the way to beat PO storm or dredge. Again, I'm saying knowledge is most valuable against decks that hinge primarily on one mechanic that you have the maindeck answers to stop. Why do people keep using shops vs blue as an example when I've addressed the minimal impact of knowledge in this matchup many times???
Also, knowing your opponent is on shops with the hand you suggested - they have to have one of chalice, one of thorn, or a sphere in hand. That's 6 cards in a deck of 60. Even if they toss out a golem, you still play 2 moxen and preordain for more mana (or draw land as well on your draw). If you mull that away because you know they are on shops, you basically give them a sphere in hand, assume that's their turn 1 play, and assume you won't draw land. That hand, if they DON'T have sphere/chalice basically wins the matchup. You are going to throw away a good hand of 7 for an unknown hand of 6 by assuming they have the sphere in hand and want to play it? (If they have only tomb/sphere or land/mox/sphere and spells costing 2 or more, they likely won't want to lead with sphere due to locking themselves out.) You basically give them the hand you fear, just by fearing it - and can mull into much worse hands.
@thewhitedragon69 That hand as described, would be crappy to keep. If they have a taxing effect you have lost immediately, thats a chance you should not take, especially because the hand isn't even good against them if they don't have a taxing effect since you are already on 5 cards (Flusterstorm and MM are dead cards). Mulligan to 6 to find a FoW and a more stable mana source like a fetch land is great.
The reason why i brought up Shops vs. Blue is especially because of the reason that you pretend that its "minimal impact of knowledge" in this match up, which just isn't true.
If i enter a tournament with a blue deck and i could choose for which match up i always get to know what my opponent is on, Shops would definitely be in high consideration.
@aelien I guess you have a point there, but I'd still have to say the knowledge of shops when you are on blue is less than knowing you are against dredge or storm if you are running wastes/rods. Sure, you can mull into a hopefully better hand against shops, but you still have to play the game and try to win. If you are against dredge or storm g1 and have the answers for their deck in your main (say sorcerous spyglass vs dredge), you probably just win on the back of one card. The knowledge in that case turns an almost definite loss into a probable win. Mulling anything in blue against shops just means you MAY have a better chance not to get blown out immediately and a chance to win if the match plays out well for you. That's less impact to me.