Okay I'm getting pissed off at you faggots for not understanding this.
What is a keystone? It's the center-piece that CONNECTS EVERYTHING TOGETHER.
When Q does a drop, he's trying to get you to connect to the dots to a particular happening. He breaks these happenings into questions so that your brain tries to connect them together.
The 'keystone' is the center-piece of information that completes the STRUCTURE of how how everything is CONNECTED.
He does this because if you understand the FRAMEWORK of what is happening, you can use that as a key to find and connect more dots around that event.
As in, it allows you to READ BETWEEN THE LINES.
AS IN, GO BACK AND READ THE NEWS MEDIA SURROUNDING THOSE EVENTS, AND YOU WILL SEE THE HIDDEN MESSAGES THEY USE TO COMMUNICATE.
Look for the KEY PIECE OF INFO in the Q drops to unlock the CONTEXT of his drop. Use that context as a FRAMEWORK for decoding the HIDDEN MESSAGES in the news surrounding those drops.
If you faggots ever played Assassin's Creed 1 or 2, they used the same concept in some of the puzzles. It's a great way to jerk off autist brains, not gonna lie.