Again, Deadpool's fellow characters struggle to understand who he's talking to whenever he addresses the reader. His asides here, especially "forget it, it's too hard to explain in one panel", poke fun at the comics' own election not to ever bother explaining why Deadpool is more self-aware than anyone else. Much easier to just pass it off as Wade Wilson being a bit crazy. I mean, he couldn't really be talking to people "beyond the page", could he?