Well, I don't know if it's a joke, but the story claiming that the Sept. 11 attack was originally intended to take place in May or June is, I believe, false. The Sept. 11, 2001, date was picked at least a year in advance. (For the evidence, see http://www.freerepublic.com/focus/news/685662/posts?page=58#58, post #58 specifically, not the whole thread.)
Notice that those Sharon and Cole stories are specifically hedged "according to KSM".
Osama barely gave a damn about Israel - he saw the big picture. And it sounds like typical after-the-fact politicization for western propaganda.
On the other hand, why not? Osama could have said "can we move it up?" Ksm-"no" Osama "OK"
IOW, no big deal, except the prominence gives it meaning.