Tiebreaking rules are a necessary evil. Tournaments, especially tournaments played over a weekend, don't have time to play extra matches to break ties in group standings. In a tournament system with no scheduling or logistical constraints, extra games would be played in the event of any type of tie. We can see this principle applied in professional sports. Baseball is a sport for which it is fairly easy to play an impromptu, unscheduled game. In baseball, an extra match is played in the event that two teams lie atop the standings of their division. However, in the NFL (as with most sports), an elaborate series of tiebreakers are applied in the event of ties, and extra games are never played. It would be unthinkable to play extra games in the NFL because of scheduling and injury concerns.
Esports tournaments have generally used the policy of "Avoid tiebreaking matches at all costs." In other words, only when there does not exist any reasonable tiebreaking method whatsoever are extra matches played. In the OSL group stages, which are round-robin Bo1 groups of four, extra matches do become necessary when head-to-head tiebreakers break down as in the instance of a 2-1, 2-1, 2-1, 0-3 group (a common occurrence). MLG's system of tiebreakers, on the other hand, excludes the possibility of extra matches: their tiebreaking system is/was something like set record --> head-to-head --> higher seed. Many tournaments have adopted the MSL system of groups (what GOM currently uses), which eliminates the need for tiebreakers altogether.
The reason for this blog is that tournaments with more flexibility in their schedules, specifically online Dota 2 tournaments spread out over many weeks, have been discarding tiebreakers in favor of extra matches and getting flak for it.
The Defense plays extra matches for tiebreaks even when a team holds a head to head advantage. Na`Vi defeated 3DMAX during group play and lost to them in a tiebreaking match. In the Defense 3 thread, joinDOTA was criticized for playing an extra game instead of using the traditional H2H tiebreaker.
Ayesee is the caster for the D2L. When I asked him about the D2L's tiebreaking procedures, he stated that the only tiebreaker after match score was "games won" and that after that, an extra match would be played. Soon after tweeting that, someone replied, Wait, where's the head-to-head?
These criticisms of the tiebreaking rules of The Defense and D2L are misguided. Playing extra matches is strictly better than using a head-to-head tiebreaker. If we have two 5-2 teams in a played out group, and Team A has defeated Team B in group play, Team B has made up that loss by defeating at least one team that Team A lost to. Granting team A the right to advance from the group over Team B is essentially arbitrary. But, as discussed above, tiebreaks themselves are essentially arbitrary (except in the case of using game score after match score, which I wouldn't consider a real tiebreaker anyway). Using H2H is a necessary evil in some cases, but many esports watchers seem to find it preferable to playing an extra match even when that evil doesn't have to come to pass! I can only imagine that this is because the long history of using H2H and its status in e- and professional sports as the first tiebreaker has left the practice ingrained in the minds of fans as the right way to do things.
MLB apparently subscribes to my school of thought about tiebreakers. Extra matches are not played to determine playoff seeding in baseball—if two teams are tied atop their division, but both will make the playoffs in any event, tiebreaking rules are used and no extra matches are played. However, the situation changes when the stakes are raised. If teams are tied and one of them faces elimination from the playoffs, MLB rules prescribe the fairest way to break a tie: an extra match.