TLDR: VCT BR 2022 Closed Qualifiers should be double elimination because there is no way to properly seed the teams, there is no finals problem (see below), and this ensures the most competitive qualification process and best viewing experience. RNG is much more dangerous.
VCT Brazil has a history of poorly formatted tournaments. I first noticed while watching VCT stage 2 where their double elimination bracket is flawed. See where Gamelanders beat Havan Liberty, lose to Sharks, but don't get flipped to the other side of the lower bracket. Instead they have to face Havan Liberty for the second time. Here is the NA bracket for the same stage where double elim is done correctly. Almost every double elim tournament in the world flips the side of the bracket that teams drop to every round to avoid duplicate match ups which are less interesting to watch and can screw teams with random seeding.
I say this because the BR 2022 Stage 1 closed qualifiers are also a bad format of single elimination. The EU, TR, and CIS qualifiers equivalent to this part are all 8 team double elim. There are many reasons why single elimination is used. It gets rid of The Finals Problem (described at the bottom) and it is necessary in big open qualifiers. However, the closed qualifiers have only 8 teams, no finals, and no previous seeding. Single elimination is extremely vulnerable to random upsets and bad seeding. If two teams are clearly better than the others but are stuck on the same side of the bracket, single elim can ruin the viewing experience. Single elim is best used as a playoffs format when teams can EARN their seeding and can't blame random chance for meeting a good opponent. (I still don't like single elim like in CS major playoffs when a lot of Finals matchups are kind of meh: Astralis vs Avangar, Astralis vs Ence, etc, but at least they have seeding).
I highly doubt the format will be changed, but the extremely limited qualification to the incredibly important group stage should not be subject to the potential for the bad RNG of single elim without seeding. If tournament gets botched by RNG, the culprit is the format.
The Finals Problem: In double elim, one team reaches the finals from the upper bracket and then plays a team from the lower side who already has a series loss. Technically the lower team should have to beat the upper team in two straight SERIES to win the championship but that makes for an entirely anticlimatic final even if it is close. Sometimes the upper team is given a map advantage but is typically not if it is a tournament finals and not a seeding game. This problem does not exist in VCT BR 2022 Closed quals because two teams qualify.
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