But that's only because Ko lost his very first game to Leonardo Didal, not to mention Mika losing his first game to Pettman.
Stuff like that will happen when the favorites lose their first games in the group brackets.
Yes, perhaps nothing is broken
I'm curious what you think could be improved. I think the first round group brackets, which are double elimination and pseudo-seeded, is as best a compromise as you can get in terms of time/table constraints and fairness. It allows players to get used to the playing conditions by allowing one loss in the early stages.
Double elimination is somewhat inefficient for table use. You need more tables for the first two rounds and then fewer later. You don't know whether a match will be 9 or 10 games or 16 or 17 games. You also don't know who your opponent is until a previous match is done. And you can't assign a table until a match is done and you see what tables are available. If you insist on prescribed times and tables, then you will have a lot of dead time on tables--time that could be used to separate the wheat from the chaff
A format that keeps all of the tables going with very little overhead time will be best. Round-robin is good because you can always have the next players waiting for the previous players-- Once A and B finish 5 games, C and D play on that table, and then A and D for 5 games, etc.
Of course the big problem with round robin is it's susceptibility to manipulation--players no longer in contention to advance can influence the fate of their opponents. So you don't want round-robin flights to get in. But that doesn't mean round-robin flights are not useful.
Instead of a 16-player double-elimination bracket (group A, for example) advancing four, I suggest the following.
Divide those 16 into two groups of 8, subgroups Aa and Ab. Do a round robin within each subgroup--say you play 5 games against each of the 7 opponents in your subgroup. This is efficient. Players play one after another on a table. Players also have breaks. But no tables go unused.
At the end of the round-robin, players are ordered within each subgroup according to how many of their 35 games they won with head-to-head score as a tiebreaker.
So you have Aa-1, Aa-2 ... Aa-8. Then there is a longer-race seeded single elimination playoff to get in--say race 13
First round matchups are as follows:
Aa-1 plays Ab-8
Aa-8 plays Ab-1
Aa-2 plays Ab-7
Aa-7 plays Ab-2
Aa-3 plays Ab-6
Aa-6 plays Aa-3
Aa-4 plays Ab-5
Aa-5 plays Ab-4
The four players that survive two rounds of this are in.