Poetry as checksums

When you're sending information over a noisy channel, it helps to send an extra byte every so often to make sure what you've sent so far was right.  It occured to me that poetry contains this redundant information, in the form of the rhyming words at the end of lines (or other structural regularities in the text.)  If the words match, you know you remembered the line correctly. This makes poetry easier to memorize and pass down from one person to the next, which was especially important in pre-literate societies.