Mostly this. I DO think that the string-thru-the-body thing has merit. The way a typical tailpiece sits loose on the studs has an effect, the way the studs fit loose in the anchors has an effect, etc etc etc. Which is why the Sustain Block is such a great bridge - fewer moving parts, and a solid anchor. BUT - either a guitar works for you or it don't. And sometimes even replacing all the 'bad' parts won't help.