I understand the how, but the why escapes me completely. After a decent amount of searching on the internet I can only find people talking about how to capitalize a title (or more importantly which words to not capitalize). Even the style guides have been mute about why they are asking us to use such a convoluted set of rules.
Is there some typographical or grammatical reason for some words to not have intial caps in a title (other than the arbitrary "because that is what is done")?