I think this could be a solution, I have also heard of giving yourself a time limit of 20 minutes a day during a specific part of the day. Or giving your password to your wife or significant other, for them to make sure you do not exceed that limit. Realistically though, it is pretty tough to manage. Since we all really want to be at zero messages in our inbox, yet are never actually there. I have been unsubscribing from a lot of email list that are less important lately, and that has helped some to keep my inbox lower.