... (besides my reply to your question in the other string).
I strongly believe that interest rates (LIBOR pegged) are going to stay low for an extended period of time. The developed world is experiencing stagnant growth and that, plus govt. auserity measures, will keep it that way. Just as Japan has seen for 2 decades, rates will stay low in that environment.
That said, BDC's are animals of the "carry trade"... they thrive on steep yield curves to optimize margins on their investments. As they increasingly exploit that... and as investors come to believe it'll stay that way for awhile as I do... look for these companies to see "P/E multiple expansion" as a recognition of that potential, IMO.