No one is telling anyone how to run their guilds.
All that was specified is the guidelines behind the rankings in this specific thread. Which stated that if you have the tag, your wins/losses will be contributed to the tag. Either you care about these rankings or you don't. If you don't, no reason to point out that it was your "b team" who lost. If you do, then no need to mock the thread that it is "serious business."
I think these guidelines should stay until the list "resets".
Personally, I think I am Legend should be high in the rankings. They field a lot of teams and they play a lot of games -- playing a lot of games means you win a lot of games. Why should losses matter? Maybe something like "if you win a game you get 2 points". At the end of the rankings you look at who has the most points, and then give bonus points for every victory someone had against guilds in the top 5. (This makes brute forcing your way to victory tough because all your losses are going to give bonus points to other guilds if you are in the top 5).