imo silvers know how to play, but that's completely distinct from knowing to play well.
Silvers understand the basic rules of the game (blue buff gives mana, red buff gives true damage dot + slow, what drakes do, what towers do, etc) but they are inconsistent with applying them. You'll see things like a level 2 kha try to take aggro w/ his top laner and dive and feed a double. He probably knows towers do a lot of damage early, but he didn't use that knowledge.
From what I've seen so far, golds are able to consistently apply this basic stuff, and they have some idea of things that are a little more "advanced" (windows of opportunity, power spikes, retaliation trades, optimal warding for different stages offensive/defensive, how to make good rotations, when/how to tp gank if top) but they aren't consistent in applying any of it. When they do, they can be very good, but when they don't, it's essentially still high silver.
Poll