Bonds have been selling off at unprecedented rates for unprecedented lengths. The yield curve as started the un-invert indicating the recession is less than a year out.
The question remains if rates will remain "higher for longer" or if the flattening will include a swift fall in rates due to recessionary pressures, possibly leading to deflation.
If Steven Van Meters and Harry Dent's predictions are (eventually) true then a play in TLT or TMF is warranted and would lead to gains in the multiples.