Remember when, during a fit of anger or a lover's spat, you could call someone a 'cocksucker' and it actually had an inflammatory impact on the individual? That no longer seems to be the case, and I believe it is due to the preponderance of cocksucking that exists in pornography today.

"Motherfucker" is slowly approaching impotence as well in the profane insult arsenal. It may be due to Rap Music, and all of Maged's Posts too, but I also believe the explosion of MILF pornographic material has had an impact. Now, if you call someone a Motherfucker, it is not always clear what you mean...Who's Mother are we talking about? What does she look like? If you have to clarify the insult by specifying -- "You BIOLOGICAL Mother Fucker, you!!" -- it just dies...

I'm disconcerted by this...

Not sure why this would be disconcerting. To me, the more socially accepted cocksucker and mother fucker are, the more cock sucking and mother fucking we'll have. If it's lack of shock value you're concerned about, you'll just need to be more creative with your profanity. This wouldn't be a bad thing either.

Try using

"Do you you suck your mother's cock with that mouth?"

The secret is to baffle them and make them feel stupid. That gets them mad as hell