Tom's just briefly criticized deconstruction in response to a student question. Tom claimed that deconstructionists believe that words have no meaning, illustrating this by claiming that according to deconstructionists the meanings of the words "dog" and "cat" are interchangeable.
Now, I'm no defender of deconstructionism, in large part because I'm very unfamiliar with the arguments that surround it and don't want to make any claims in a debate that I'm not familiar with. But from the little I understand I think that Tom's characterization of deconstruction is rather unfair. Instead of holding that words have no meaning, deconstructionists, I believe, make the much weaker claim that words have no *fixed* meaning, and that the meanings of words alters between speakers and listeners. And this doesn't seem that bizarre to me.
Incidentally, for a really nice--and amusing--account of deconstruction, read Morris Zapp's synopsis of his (fictitious) paper "Textuality as Striptease" in David Lodge's wonderful novel *Small World*.