Prevailing wisdom is that to be a top player you have to run a 30 card deck. Any more than that and you're diluting the deck and creating unnecessary inconsistencies.

Prevailing wisdom is that certain cards (Eladwen Frostmire, then Portal, then Sandra) are overpowered and need to be nerfed immediately.

Prevailing wisdom is that if you're a high rated player and you are facing a deck you don't like or get a crappy draw quitting the game is a perfectly acceptable means of ...