I think looking back at what the original law-makers intended is useful in that it removes the veneer of respectability that something 'enshrined in law' might otherwise have, when people more respectable and revered (authors of the constitution) are shown to have doubted and questioned their (patents) validity. Lastly it shows how far we've come in a (relatively) short time. From "very peculiar cases only, if at all" to inalienable, perpetual rights that monied interests have over ideas.