Total return refers not only to the interest you receive on your fixed income investment but also the change in market value that comes mostly from expected changes in interest rates.

I am not familiar with total return curves, but presumably you could plot out total returns--especially of bond funds--compared to published yield curves. This would give you a measure of market mood: either pessimism or optimism, and may signal good times to buy.

However, this concept is for those who trade bonds or bond funds for short term profits. Ie, this is a market timing device. Fools believe in mechanical investing rather than market timing. Laddered maturity bond portfolio is one of those. You avoid market timing decisions.

Given the strong signals that come from the Federal Reserve bank, interest rates may at times be somewhat more predictable than other market forces. However, no one--not even the Fed--really knows when rates will peak or valley. Its still market timing.