The present yield spread over Treasuries is also below average.

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Some may argue that the present, wider high yield spread is a function of the low Treasury yields, but historically there has been little correlation between the spread-versus-Treasuries and nominal Treasury yields.

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At present, most high-yield companies are covering their interest, as evidenced by the U.S. default rate.

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In any case, if Treasury rates rise substantially from their present level, history strongly suggests that high yield bonds will be comparatively well cushioned.

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The conclusion seems to be that investors are not being paid well at present to take the incremental risk of high yield bonds over Treasuries.

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Crucially, it states that the present value of future liabilities must be calculated by using the yield on long gilts as a discount rate.

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The requirement, drawn up after Robert Maxwell robbed his companies' pensions funds in the early 1990s, attempts to assess the present value of pension funds' future liabilities, taking the yield curve on gilts as its reference point.

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The team thinks all of these factors present a catalyst for investors to enjoy the higher current income versus investment grade and potentially for the yield advantage to compress further leading to modest capital appreciation.

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But given our present technologies, it would take vast changes in our ability to reach for the heavens before either endeavor could possibility yield a profit.

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