“If I am to speak ten minutes, I need a week for preparation; if fifteen minutes, three days; if half an hour, two days; if an hour, I am ready now.”
Woodrow Wilson
For those of us whose work involves talking in front of groups, brevity is the hardest thing. I used to think the opposite, that the hour-long keynote and the 45 minute sermon were products of weeks filled with grueling preparation by an expansive mind. But I find now that talking for a long time makes me less nervous than talking for a short time.
A short address requires many, many more decisions by the speaker than a long one, which might make it a very useful appraisal of leadership. After all, that’s what we asked you here to do: make decisions.
YoRocko! 
This is a wise point, Rocky, that not enough people know about. I tend to have mental lists running about “You wanted this, so there’s no time for that” (“This” and “That” being the competing topics. I think of these like what my favorite writing books call “reading like a writer” — but “speaking like a speaker” doesn’t have the same ring to it. Sigh.