Two questions on Quickness -- Special Smite-o-Mat Recipe

[tinkthank]

Quickness is exactly what?

- It doubles your in-combat AP
- It increases your in-combat AP by a factor of X (X = ?)
- It doubles AP spent on spellcasting and increases other AP by a factor of X (X =?)
- It does something different?

I can't figure it out by watching battles. It seems good. I usually rush for alteration 2 (I think?) if I have any water mages, it just seems so tasty.

But I am wondering now about the Boots of Quickness.
I have a nice Absysian Salamander prophet who was lucky enough to get Heroic Quickness as his Heroic Ability. I am have been wondering how to equip him. You can imagine that I am interested in giving him lots of Reinvig items. Especially since if he's in a province with say Heat 1 or even worse, he'll be sweating. Or whatever it is salamanders do when they are fatigued.
Oh yeah. But what about the feet? Messenger boots / Boots of That Druid Guy -- or Boots of Quickness?

So:

- Do Boots of Quickness / Quickness spell increase the net BASE AP rate or the gross increased AP rate (of Heroic Ability) (oh please please yum smiteorama yum yum) -- and if so, by how much (see above question)?