You know the mantra around here: Everyone's situation is different.
For a while there, I was splitting my nonstock portion between the total bond fund and the stable value fund in my 401(k). It seemed a good idea at the time. But when the stable value fund return dropped considerably and the long-promised higher interest rates didn't materialize, I gave up on that approach. So much for my tweaking. I now plan to just stick to 60/40.
"Wealth consists not in having great possessions, but in having few wants."