dwbogle wrote:Should one be concerned with the portfolio diversification of Fidelity Total Bond Fund (FTBFX)?
24.8% MBS Passthrough
This seems like a lot of exposure to risk especially when you look at Vanguard TBM (VBMFX).
You can't compare the two. It's an apples to oranges comparison. Fidelity Total Bond Fund is an actively managed bond fund and contains undesirable stuff (ABS, CMBS, CMO). Vanguard's Total Bond Market is based on the Lehman Aggragate Bond Index.
The equivalent Fido fund is US Bond Index (FBIDX).