Just a bit of background on all of this:
Powerplay is used to lower the clocks of your cards when you are not using it to its full potential in 2D applications (browsing the net, Microsoft Office, etc.). This decreases the power drawn by the card and reduces the heat generated.
It seems like running GW2 does not change the mode from 2D to 3D. Now I finally realize that some of my crashes in the game are due to this because the card fan speed in 2D mode does not adjust to the temperature very well (causing a hard crash requiring reboot). This is a big issue because high temperatures reduce the lifespan of the graphics cards.
What this tweak does is that it increases the default 2D clock rates to values similar to the 3D clock rates. However, this means that your card is running at full capacity at all times. I’m also not sure how it scales the fan speeds(my biggest issue) but I will take a look.