There is no sport that can even be applied as an analogy to raiding, it's really not relevant. World first races are very specific to WoW and the rules and customs surrounding it are not directly comparable with anything else.
One boss kill isn't enough to determine which guild is better, but if I had to pick, the guild that killed it first. The guild that puts in 300 attempts has probably done so before there is any information out as guilds who aren't interested in being secretive about their progress aren't even there yet. The guild killing it in week 3, even for Ra-den, will have access to hundreds of hours of streams and other information that has become readily available by that point.