One way of looking at a swiss tournament is that X players play magic, and eventually the 8 best records make it in. That model for a tournament leaves you with the baseline strategy "maximize match wins."
On the other hand, you could also say a swiss tournament is one in which X players play magic, and if you end the day with 1 or fewer losses, you make top 8. (This is true for most, though not all player counts). This model of a swiss tournament suggests an entirely different strategy. You get to have one loss. If you don't take it, you'll finish higher in the standings and get to play first in the top 8 ... but you have the OPTION of "spending" that loss. It sounds crazy to throw away a game on purpose, but that's not quite what I'm saying. Your loss is a resource you can spend for an upside.
A classic example here is "The Dredge Gambit": opting to run zero anti-dredge cards in your sideboard in a field where you expect a dredge opponent. Assume for argument's sake that you're playing a deck that is very unlikely to win the match without a sideboard. Essentially you're gambling your swiss loss against extra sideboard cards for other matchups. In some cases, this is the right move - even if you DO get paired against Dredge and lose to it.
More subtly, you can spend your swiss loss on playing a less consistent deck. You can afford to take one manascrew loss in a tournament, or one "drew all my Grindstones and no Painters" loss. People are basically making this gamble all the time without realizing it. Deciding not to run free counters means you're spending part of your swiss loss on
Of course none of this is discrete. you're not literally taking a loss to run a more powerful deck, but you ARE changing your odds of taking a loss in particular situations, and you're getting a benefit or penalty for making that choice. This isn't new to magic strategy, we think of cards and in-game decisions in probabilistic terms all the time.
Consider how all of this changes with other tournament structures:
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Would you run the Dredge Gambit in a round-robin tournament where it's impossible to dodge any dredge players who show up?
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Would you run the Dredge Gambit in a single-elimination tournament where you would HAVE to dodge dredge entirely or be eliminated?
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Would you run a transformational sideboard in a tournament where decklists were given to each player before the match? How about Cabal Therapy?
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How many rounds does a tournament have to be before you start worrying about fatigue from playing a decision-heavy deck. Are you less worried about that if the tournament has a lunch break?
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If you were playing in an event entirely composed of players you knew pretty well, would you metagame specifically for those players rather than global/online metagame?
Now realize that your typical vintage tournament isn't really a swiss tournament at all. It's two tournaments stacked on top of each other.
One of those tournaments is swiss. You get to take a loss safely, the tournament is probably a mix of strangers and familiar faces - with larger events consisting mostly of players you've never met before, and have no information about. It's multiple rounds, and if you don't play anything too slow, you can expect at least one of those rounds to have a reasonable break between them.
The other tournament is 3 rounds, single elimination. If you've been doing your job you know what the other 7 players are playing, and you have a pretty good idea of which of those 7 players you'll have to beat. Chances are pretty good that some number of people in the top 8 are people who frequently in your region - people who you could have predicted doing well before you chose your deck, sometimes people who don't mix up their strategies very often. Usually it's held at the end of a long day, with lots of spectators, right in your opponent's eye line, making very little effort to hide their reactions to cards they see you draw.
There are different strategies to optimize you chances in either of these events - but you have to pick the same deck for both of them. It is absolutely possible to make a decision to maximize your performance in the swiss at the expense of your top 8 chances, and vice versa.
And this is just one aspect of tournament-specific strategy as separate from magic playskill. Proper mindset and avoiding tilt is a lot harder for most people in a tournament situation than it is during testing ... tiebreaker math can be VERY complicated ... the ability to talk to judges and call them when appropriate is MASSIVELY important and underrated ... bad logistics can undo months of testing ... mind games are overrated, but definitely real ... rapport with unknown opponents, even just generally being a nice/classy player can be pretty critical when the top 8 is talking about a prize split, or you're paired down against a player who isn't in contention for prizes anymore. All of these things are real edges, and magic players love talking about edges.
If this topic is at all interesting to you, I strongly recommend reading Theory Games . I don't hear people talk about this one, but I rate this in my top 2 or 3 favorite magic articles of all time. The high-level summary is that since magic prizes are not evenly distributed, a strategy that optimizes for winning MATCHES is not as good as one that optimizes for winning TOURNAMENTS/PRIZES. You'd rather go 8-0 to win one event and 0-8 in four events, than 5-3 in five tournaments, getting no prize each time, despite winning twice as many matches. It's truly brilliant stuff, Karsten is playing this game on an entirely different level.
Of course, every single thing I've said in this post is absolutely DWARFED by the edge you get from learning to play just a little bit tighter. It's fun to talk about this stuff, but I wouldn't worry too much about it if it isn't your strong suit.