I agree with Rubick that sanctioning the rhyming of many with plenty and twenty is a gross injustice to the language. However, in instances of "off-rhyme", even the classic poets have be known to stretch it a bit in a pinch.

Oh, I'm not implying at all that it shouldn't be used within a poetic context. Keiva's excellent example of ryhming paws with sauce is one such instance with which writers have cleverly manipulated words over the years. What I am 'moaning' about is that a reference book gives examples of such incorrect usage of words. Pairing twenty with many is akin to giving a false definition in a dictionary. IMHO.