[rjd]

The problem with silent+no vibrate is that interruption still exists. I often take my phone out of my pocket when sitting for dinner, or just randomly when I become aware its there.

What I really should do, and might do after writing this is trying and balance the notification messages. reduce them to have no context at all, hopefully I wont accidentally read them.

But the real problem is once I have a problem on my mind it bugs me to I solve it. It takes over my thought processes and annoys me, and when this happens while I'm out on a stroll or out for dinner, I'll spend the rest of the evening thinking about it.

[sliverstorm]

There's a variety of options. You could, for example, turn on and off email notifications completely, to the tune of your schedule. (You might need Tasker for that though)