Partly I used that preamble for politeness. Politeness DOES matter. Hopefully phrasing it that way will make it more likely for others to consider what I say rather than to just immediately get defensive as they would were I to phrase things rudely.
Yes, I understand your intention, but for my part I find those preambles to make what you say less polite. Opening up with, "I don't mean to be rude, but...", to me is even more irritating and provoking than often what follows. This is because too often, people who use that sort of preamble, do mean to be rude, and obviously know that they are being rude, but not only persist in their rudeness despite knowing how they are going to come off, but are being passive agressive about. They treat such preambles as a free pass that somehow excuses them of whatever they say. Indeed, I've concluded that in many cases, the real meaning of those preamables like, "I don't mean to be rude...", is actually, "I do mean to be rude, but I don't want to think of myself as being rude, and I don't want other people hearing me being rude to think of me as someone who is rude."
In other words, I find that the phrase compounds error with self-deception, pretence, and dishonesty.
Whereas, without the preamble, I might simply think that the person is not meaning to be rude, is unaware that it might be taken as rudeness, and so I'll give them the benefit of the doubt. Or at the worst, I'll assume that there rudeness is intentional, but is only a sort of immature attack on my character or person that no one will really take seriously and which is indeed likely to reflect badly on them. Somehow, giving such an attack a preamble makes me feel that its potentially more damaging, in that it seems like a well played trick - a foul deed hiding behind a fair face.
And the same generally seems to hold true for all similar preambles where people try to deny that they are doing what they in fact (at some level) know they are doing.
I admit that it irritates me more often than it should, and, in your case in particular it didn't irritate me very much because I assumed from the content that followed that you meant it as politeness, but sometimes its that false pretence of politeness that is precisely what I find most impolite. Besides, "I don't mean to give you my opinion, but I will..." is more funny than irritating.
I gather from his writings that Tolkien had the very same issues. In fact, the Hobbit opens with a discussion of almost this very problem. Bilbo is being rude, but hides his rudeness behind false politeness, so that Gandalf says things like, "My what many uses you have for 'Good Morning'. Now you mean that it won't be a good morning until I go away." And Sam in particular, every time he is about to do something stupid and put his foot in his mouth, begins with a preamble where he denies (to himself) that he's doing exactly what it is he is doing. For example, when Frodo is speaking to Faramir, Sam is increasingly thinking that Frodo is being foolish and Faramir being unkind, so in response he says, "I don't mean to put myself forward...", while stepping in front of Frodo and placing himself at the center of attention (and shortly thereafter making a fool of himself).
I have no desire whatsoever to convince other people that I'm right and they're wrong. I know that there is NO right way or wrong way.
My opinion is similar but different. I believe that there are things that are right and things that are wrong, but for many activities most choices are matters of taste so that there is no ONE right way.
