I have been playing disc golf for a little while but only until recently have figured out how to throw properly. It's definitely the most important part of the game and it takes a lot of practice. Grip and stance are everything.
I'm not exactly sure what your question is, but I will say that the power grip is definitely what you want to do. What I did was play around with it a little bit to see how you can get it comfortably in your hand/fingers. I found that even a slight tweak can make a huge difference in the effectiveness of your throw and technique.
It is important to get your finger pads on the inside rim of the disc. I have taken to fitting the disc in the crease of your hand and fingers, and making sure your grip is comfortable yet strong so your disc is not flopping around in your hand. I even tend to put a bit more pressure on my index finger's grip to add strength and direction to my shot. Keep your thumb in line as it naturally sits with your grip. Don't squeeze your thumb flat on the disc, just let it grip regularly. Also you only want to fan a finger or fingers when you are doing a control shot with less distance.