I'm pretty sure you haven't been able to save pages like that. As a collection of re-referenced files, sure, but not as a binary-encoded URL. Maybe the mac had the ability to save into one file or something, but it's still a file, not a url. URLs have a magical place in the world of html - you can link to them, etc.
As for syncing to the desktop, yes you can do that, but I imagine only safari on the desktop could load it. In fact, the recommended way of getting the linkstring onto your iphone is to do it on the desktop and synch it, so i imagine it works both ways.
And you are cheating. I say it's a cool engineering hack. And you say it's not cool because it's a workaround. I'm not talking about it as a workaround. I'm talking about it as a self-contained hack. I happen to find it cool that I can save an entire page, pictures and objects included, into a single text string that, theoretically, I could type into the address bar and have the page render correctly. The guy did it with a 350k long url, and it worked. That's just neat. It's just as neat to be able to do that on the desktop. It opens up all sorts of possibilities. It's like capturing the state of the browser and being able to resurrect it.
In fact, I bet I could fairly easily generate new images on the fly on the client side by generating the appropriate strings. Hmm. Opens up all sorts of fun ideas.