Leeks

“How to save a life” by The Fray is literally intervention instructions.

Sure. It just means you got a drinking buddy!

It sounds more like you want a cross posting feature. There is no reliable programmatic way to determine both threads are about the new show, and anything that’s not reliable and programmatic is just ripe for abuse.

A cross posting feature would be nice, but for something like “the new episode just dropped” without some serious coordination between the communities, you would still end up with a lot of threads.