One failing, which I think it's significant, is that pages which are written as authoritative do not specify where they derive their authority from. Specifically, what I'm thinking of is finding information that says something is obligatory or forbidden but doesn't say what laws/rules/customs/departments make this the case. More links to legislation.gov.uk would improve the democratic status of the website.
The IRS does this too; you can ask the IRS for their opinion on a tax matter, and they can give you a letter that states their position; which is a defense if you follow it, but it's not necessarily how the courts would rule. Many times it is worth following the letter of the law and being ready to defend it in court.
