I don't get it.
According to this article from SmartMoney.com called
The Living Yield Curve, an inverted yield curve occurs when long-term investors are willing to settle for lower yields now because they think rates and the economy will go even lower in the future. Hence, they're betting that this is their last chance to lock in rates before the bottom falls out.
Okay.
But in the past all of the inverted yield curves have occurred with long term bonds yielding much higher rates than today. Why on earth would anyone want to lock in 30-year rate in the low to mid 4%s?? Historically, 30-year interest rates have never been that low. To think they're heading lower seems like an unrealistically pessimistic view of the future.