I guess my only comment would be that with the introduction of education under fair dealing, there needs to be a reconciliation of this clause with the need to have a balance between fair dealing and the ability to pass on to students extracts of copyrighted material without infringing the law. So again, there's a balance: here you're saying, on one hand, “destroy all those things after 30 days”; on the other hand, we're saying that fair dealing in the context of the classroom allows us certain exemptions.
On February 28th, 2012. See this statement in context.