It's being more honest with yourself and your own beliefs, though it certainly isn't more honest with your fellow bar patrons.

If you have a thing against lying (and I do), it's the lesser of two evils.

The inspiration was from professor Robert Thornton of Lehigh University, who came up with a creative way to write student "recommendations" that, if read literally, said quite directly that hiring this particular student was a very, very bad idea. If read figuratively, however, they sounded like glowing reviews, and indeed if you were expecting a good review you would think it were an absolutely wonderful review.

This was necessary because as a professor he was obligated to give students recommendations for their employers, but negative reviews have resulted in serious lawsuits in the past. Unwilling to compromise his morals, he got very creative with the English language instead of lying.

In that case, the reviews weren't meant for the student to ever see, but that is often unavoidable. He certainly did hope that the student's potential employer was capable of reading between the lines and comprehending the message.

He called his system L.I.A.R., if you want to search for it. They are pretty funny, and really do sound like positively glowing reviews until you look at exactly what they are actually saying.

One reason is because dog-whistles can work: I have from time to time had the experience of expressing my opinion about a subject in a way that causes the minority who agree with me to recognize me as a potential ally without triggering reprisal from the majority who disagree with me.

Another reason is to preserve some credibility in case of a future discussion where I'm more willing to deal with the consequences of public opposition. Rather than having to say (for example) "Well, yes, I know I said policy X was a good idea, but I didn't really mean it; I was lying then, but you should totally believe me now because I'm totally telling the truth" I can instead say (for example) "I said that policy X is an efficient way of achieving goals Y and Z, which it absolutely is. But I don't endorse maximizing Y and Z at the cost of W, which policy X fails to address at all."

Yet another reason is to use plausible deniability as a way of equivocating, when I'm not sure whether to come out in opposition or not. That is, I can disagree while maintaining a safe path of retreat, such that if the degree of reprisal I get for disagreeing turns out to be more than I feel like suffering, I can claim to have been misunderstood and thereby (hopefully) avert further reprisals.