[quote=@Shienvien]
If we're going to make tab/shift-tab distinction, then I'd rather tab was the whitespace character and shift-tab the whatever keyboard navigation thing Captain  mentioned.
[/quote]
The shift-tab key should produce the white-space character since the tab key is reserved by the browser and by operating systems for keyboard navigation to the next form component, and making the tab key produce the white-space character would obviously conflict with that.