Kaspian - Your post seems more relevant to the thread about oil investing.
If you want some ideas to try instead of an actively managed bond fund, these are all available at Vanguard:
* municipal bonds in your state. If you have a high tax state like CA or NY, this might help with taxes. But it also focuses your bonds near where you work, and could concentrate your risk.
* diversified municipal bonds. Especially with something like Vanguard Tax-Exempt Bond fund, this can be reasonable. It's exempt from Federal US taxes, and diversifies across states.
* Certificates of Deposit (CDs). If you're afraid of interest rates, there's CDs paying 2.00% (as of this weekend). Once you start the CD, you earn the listed rate of return even if rates drop. If rates rise enough, you can take a penalty and reinvest. Tax treatment is usually worse, though.
* You could buy US treasury bonds through Vanguard. These need no diversification - they are backed by the full faith and credit of the US government. Unfortunately in January the 5-year notes fell 0.50%, so they're not as good a deal today as they were a month ago.
Oh, and yes I know about treasurydirect.gov, where you can also buy treasuries. But I hate the interface, I hate the virtual keyboard, and I hate their 2-factor security. If you like it, more power to you.