First things first. If it ain't broke, don't fix it. If you are getting good shaves out of the grip you are using, don't fret if it isn't the standard grip.
That said, I have a question about the grip you said you have trouble with. I tried holding my razor as you describe, and it also felt awkward and lacked the control I have with my normal grip. I hold mine like this, which gives me great control:
http://straightrazorpalace.com/srpwi...0px-Grip_1.jpg
It sound to me like your middle finger is where my ring finger is, and your pinky finger is not being used. Have you tried it like the above pic?
However, I usually use the side grip you use when I go ATG.