How can I can start to understand this post-ironic avantgarde humour of [s4s]?
Its hard. You have to study music theory first.
It's like sh*tposting on /b/, but it's funposting - be friendly and try to be more ironic than the next guy. Attempting to force a meme is a meme in itself here.
Just think about that for a second. Let it settle in.