User:Camembert/Double redirect

There seems to be a great deal of confusion amoung some users as to exactly what a "double redirect" is and how one goes about fixing them. Becuause I'm a public spirited kind of guy (and because the thing I was supposed to be doing right now has been cancelled), I hereby offer up the following pointers which may help to clear up any misapprehensions.

What a double redirect is not

First of all, here are some things that are not double redirects:

• Page X is a disambiguation page pointing to article Y among others. Article Z links to X. This is not a double redirect, it is an ambiguous link. If you edit article Z to point to Y, a reasonable edit summary might be "disambiguating X". The value of such edits is high, since they cut out an unnecessary click for the reader.
• Page X redirects to article Y. Article Z links to X. This is not a double redirect, it is an ordinary redirect. If you edit article X to point to Y, a reasonable edit summary might be "avoiding redirect". The value of such edits is low, since a link which arrives at its destination via a redirect works perfectly well.

What a double redirect is

Here is what a double redirect is:

• Page X redirects to page Y, and page Y in turn redirects to page Z. This is a double redirect. If you edit page X so it redirects straight to Z, a reasonable edit summary might be "fixing double redirect". This value of such edits is very high, since they cut out an unnecessary click for the reader and avoid the reader seeing an uninformative and confusing redirect page.

Note that if in an attempt to "fix" double redirects you do not edit page P to redirect directly to R but instead edit all the pages that link to P to link instead to Q or R, a suitable edit summary would be "I am an idiot", since you are clearly an idiot. This greatly increases the amount of work you have to do, and doesn't even fix the double redirect—even if you remove all the links to P now, there's no guarantee that somebody won't link there in the future.

What causes double redirects?

Contrary to popular opinion, double redirects are not messgaes from aliens, and they cannot be avoided by donning tin-foil hats. Nor do they have anything to do with stem-cell research, asylum seekers or the forces of communism. They are usually caused by page moves.

Somebody writes page Y. Because X is the British spelling for Y, they make Y redirect there. Later, a different user comes along, and (possibly contrary to a consensus reached five years previously by three users, two of whom are now deceased, possibly not, we just don't know) moves page Y to Z. The software automatically creates a redirect from Y to Z, thus creating a double redirect from X.

This is why when you move a page you get a message saying "". This does not mean