“With all due respect.” The phrase is supposed to acknowledge that the parties of a conversation do not agree on a particular point, and such disagreement is not due to any disrespect. It further indicates there is a degree of admiration due to the listener.
A skillful speaker of English, however, can successfully twist the phrase into a slight in and of itself. The truly beautiful part of using it against the listener is that there is nothing in particular about the phrase that should engender anything from the listener other than a polite response; it almost creates the obligation for a polite response. If you’re the particular sort who takes great pride in knotting someone’s boxers in a bunch, you can lay that on your listener, say something that completely contradicts what they have just represented and they will be left with the sense that you were speaking to them with respect, yet you have come up with something utterly offensive.
This of course can cost a few social points in that you have specifically stated that you don’t mean to be offensive – and clearly because you gave all due respect – and yet your own social filters were unable to screen out the patently offensive comment. However, if the target of your social incorrectness is somewhat more socially inept than are you, you can easily skate on this point with all of your social correctness chits in place.
You can also use the phrase to indicate how little you actually do think of the listener.
When speaking with someone you clearly do not respect, stating that you’re going to make a point to them with all the respect due them, is a bit like offering the sleeves off your vest. Say you’re talking to someone with whom you are actively engaged in an ad hominem attack. In the phrase “with all due respect,” you’ve now embedded the meta-message, “and you’re not due any respect.” “With all due respect, I think you’re a pusillanimous puke.”
In my opinion, the most personally satisfying use is the time when the object of ridicule has no idea he or she has been identified as not having been due respect AND having received the offending comment having been initially disarmed by the that initial faux-acknowledgement. It’s a beautiful Machiavellian double-entendre where that individual may actually compound the insult by acknowledging that what you have said could be true.
The skillful turning of a phrase can be one’s best psychological defense from perceived attack or one of the best implements with which to bludgeon one’s despised other in a socially tactful way.
And so, with all due respect, I must now bid you adieu as I do have some other affairs to which I must attend. My hair needs washing and my socks are due for their matching. I’m sure you understand.