Our own Justin E. H. Smith in his eponymous blog:
Why are palindromes so far down on the hierarchy of literary genres? Roughly speaking, they seem to stand at the same distance from the rigorous formal experiments of an author like Georges Perec as bawdy limericks stand to Shakespeare's sonnets. This may be due to their own inherent tendency towards bawdiness, which I think can be explained by the fact that one must make use of concise, monosyllabic grunt-like words, and these words tend, at least in English, to be both part of our core Anglo-Saxon heritage, and generally to denote less than lofty things.
At the same time, the formal restrictions imposed in palindromy do exactly what Perec's did, exactly what makes restrictive rules of composition interesting: they force you up to the boundary of meaninglessness, and so challenge you to find that acceptable level of near-nonsense that nonetheless seems to say something.
To speak for a moment not of palindromy but of homonymy, years ago I heard the spoken sentence, “A strict syntax limits semantics,” but understood by this that “A strict sin tax limits some antics.” As it happens, both are true. Now I think orthography is a sub-syntactic feature of sentences (perhaps someone can fill me in here), but the principle is the same: it limits the range of things that can be said.