I've posted a discussion on [MSO](https://meta.stackexchange.com/questions/103366/dont-show-links-that-are-not-currently-available) with the same title (but the title was changed). It's about disabling elements that can be clicked but lead nowhere. For instance dead links. Currently, the 404 error page is shown.

One of the [comments](http://www.joelonsoftware.com/items/2008/07/01.html) implied that leaving the elements enabled can actually be positive.

I've always thought that disabling elements that cannot be used was the correct way to prevent users from wasting their time, but maybe there's other evidence. If so, do you know about it?