I don't understand why anyone would deliberately make a website with such simple navigation completely hidden.

I am very sorry about unintuitive interface, but these are slides for the talk I gave on nodecamp.eu, not a website.

I'll add a note on the first slide as soon as I get home.

Ah, I see.

When using the same website both for the actual presentation and for disseminating the slides afterwards, it might make sense to have some kind of navigation visible by default. You could then have a "presentation mode" shortcut key that hides the nav element when you're showing the slides on the big screen. This way, the same site would serve both audiences.