When they bury you inthe end if the worst thing said about you is "He was a sound conservative engineer" by my take I would say you have done all right.

DLF is influenced by period you might be able to cut down the DLF by looking at some natural frequencies. But yes ther3 is a DLF as the Dog wags its multiple small tails...

Take a read on this for some thinking....http://www.coade.com/newsletters/dec98.pdf