I have read in a number of different places (here’s one) that you should not have your email client notify you as soon as email arrives — check once every hour or half hour or even less often because it takes your brain more than a minute to get back into its train of thought after being interrupted. Hogwash.
Let me clarify — if an email arrives that requires your attention (i.e. you need to respond right away or immediately take some action), then yes, I can see it taking a minute or so to get back into what you were doing before. If handling the email takes an hour or more, it may take even longer. But speaking for myself, I get emails all day long, and the majority of them are either not relevant (i.e. another developer notifying me (as part of the entire development team) of a bug he fixed in a module that I never use) or not important enough to stop and deal with immediately. In those cases, it might take me five seconds to get back into what I was doing. Given the number of 5 second interruptions I get, I’d have to be sitting at my desk in a daze for many minutes at a time to get my average interruption time up to 65 seconds. While this may be true on some days, it’s not related to email.
Irony: While writing this blog entry, I received an email. I stopped, read it, decided that I could deal with it later, and then came back to this. My first thought was “Now, what was I saying? Oh yes, something about email.” It still only took me a few seconds to remember what I was in the middle of saying, but it did strike me as kind of funny.