I don't think Chris is intellectually capable of analyzing implausibility. I would describe him as mentally damaged in that way. It specifically is a binary thing with him.
We're also very good at framing our requests as "normal". Like I forget who it was, but one egirlfriend had an open relationship with Chris. That, on its face, isn't that big a deal. But once we got Chris to OK it, we kept slowly increasing the stakes, to the point where it was something like the girl was cucking him with some big black dude and rubbing Chris' face in it. It's like
boiling a frog.
And then on top of that, even if Chris was a bit smarter, grew a pair and said "no" a bit more often, our techniques are sufficiently flexible to the point where we'd still get content out of him. It'd just be slightly less funny content.