[jasontsui]

Fun pattern, but is it more useful? I think its hyperbolic to call losing 160px of reading space on top of a desktop browser a "nightmare". Something a user can see all the time has greater affordances than something that is hidden. Especially if that something is as essential as navigation. Honestly, I think this is more style than usability.

[SilasX]

Yes, losing 25% of the already-scarce vertical space is a nightmare, to the extent that UX can be a nightmare. Plus, I've seen sites where the nav bar locks the URL bar in position and keeps me unable to scroll away from it, making it more like 50%. It's like I'm looking at the site through blinds!

And it's all for functionality I'm not even going to use!