Oh, I dunno about that. Do a youtube search of some of his pre-"Muppet Show" and "Sesame Street" stuff. I was watching some bits the other night, and was amazed that it snuck past the censors.
He also did a fair number of commercials back in the 50s and 60s - again on youtube. Some of them are laugh-out-loud funny, and you can see a lot of The Muppets in them.
The key thing is that it was innuendo or maybe a double-entendre at best. Those things got adults to watch while keeping it rated G on the surface for the kids.
Certainly no profanity or outright sex talk.