Leave the past in the past: Should you also prune the tens or hundreds of thousands of messages you've already saved? For me, the answer is no, because having to think about each of them long enough to decide whether it should go or stay would chew up far more of my time than it would ever save. If I can delete hundreds in one fell swoop — for example, if all the messages from a certain mailing list were also available in a Web archive somewhere — that's one thing. But otherwise, selective culling just isn't an effective use of my time.
Archive locally: However, it is fair to ask whether all those messages need to stay in my email client and on my IMAP servers. They almost certainly don't, and you can reduce the amount of time your email client spends syncing with servers (as well as recover server storage space) by using an app such as Pubblog's $100 MailSteward Pro () or one of its less-expensive siblings, $50 MailSteward or $25 MailSteward Lite to archive older messages locally.
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