I wonder if the shortcut should be removed. Certainly some people use the feature, but it seems obscure enough that maybe we should pass that combination on to the website, instead.

The feature is rather useful for record-keeping purposes (also known as CYA).

Though you get an html file and a folder with all the external assets, which I find to be pretty annoying. Safari did a single .webarchive file, but I don't think anyone else ever standardized on something like that.

It often wrecks the layout, but I tend to print to PDF rather than deal with saved html files.

Save-As writing bunch of resources, that when loaded back into the browser might even be broken by lack of external resources are also, in my oppinion, a bad way to keep evidence (e.g. CYA). If you need it to persuade a non-computer-savvy person of something stated on a website, I'd say a bunch of random files in a directory is also much less convincing than a "printed-to" pdf, or screenshots you can easily mail around.

Regarding the .webarchive, I think IE supports another type of "web archive", with a .mht ending.

Opera and IE support MHTML (MIME HTML), it seems to work alright