If you can afford it, "sleeping on it" -- an idea, a draft, an important email, a response -- sounds like great advice.
The reason I'm bringing this up is that I was baited into reading through a mostly inconsequential blog titled "Always Sleep on Emails Before Sending Them" [here]. My hopes were set too high and I clicked too fast; there is nothing in the referenced article that delves into the reasoning behind the concept. It's a missed opportunity if you ask me. I suspect that a lot could still be said about intentionally delaying one's actions in order to decrease the risks and/or increase the efficiency associated with the said actions. Let's hope that someone competent will complete the thoughts of the author and finish the job, one day, soon.
In an era of instant communications where timing even the most mundane of tasks has risen to the level of a critical survival skill, sleeping on anything is rarely a viable option. The more tasks you have in your queue, the more likely that sleeping on anything will place that thing in a state of limbo from which it will never recover. Take me as an example: I typically do a lot of that "sleeping on it" thing. This explains why there are a lot more blogs and articles pending than there are published. Most of them will never wake up.