So today I tried using PulseAudio Dynamic volumes again, and the quick conclusion is this: They are bad, so very very bad.
Previously I had been cruelly subjected to Dynamic Volumes on with my Desktop through it's several speakers and sub-woofers. Now I tried it on my laptop using headphones / earbuds. The experience was actually worse.
On the surface Dynamic volumes seems nice, because in theory it should raise the total volume of the system as necessary. There is however one drawback. It raises the MASTER VOLUME for the entire system, which means all other applications and any subsequent applications will inherit that volume level.
So say you raise the volume on a piece of music you are playing (in Amarok for example), which is nice. They you load a video in your VLC. The video's audio is louder to begin with AND the VLC volume is set to the previous amount, which was 140%. Suddenly your ears are blasted with maximum audio volume. Painful and wrong.
Seriously. I'd fucking sue a company for earing damage if this wasn't free software with absolutely no warranty. (Okay, I wouldn't sue an open-source free company, even then, because I love open-source, but you get the point.)