Uh...
3 hours for a 20-person double-elim bracket is
extremely ordinary for any game. That's a 11-stage event! On 4 setups, that's 13 cycles.
180 minutes for a 13 set event is... extraordinarily mundane.
At even a modest 66% efficiency, that's barely 9 minutes total playtime for the average longest set in each round.
As a TO, I would schedule a minimum of 210 minutes for a bracket of that size in either Melee, Brawl, or Smash 4.
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Monday night I had a 3-stock Smash 4 tourney for people who didn't drive to Apex. Our 14-person double-elim bracket took 2:20 total. This was in spite of running 3 stocks, having almost every set go to game 3 (it was crazy), and having a reset in grand finals.
This was only possible due to two facts:
- Excellent Efficiency (Good TO match assignment)
- Smash 4, including 3 stocks, not actually taking long
I've said it before, and I'll say it again:
The impact stock count has on match length is negligible compared to station efficiency, set length, and tournament structure.
I do not have a strong preference for any particular stock count, but I do have a strong preference for facts being correct and decisions being made for the right reasons.