I honestly don't know how the Magic Mouse is meant to be used for extended lengths of time. The touch surface means that not only do your index and middle fingers need to be held hovering above it, but the rest of your fingers also need to claw in from the sides to keep overhangs of skin from triggering stray cursor movements. It is truly painful to use.
Maybe you used one with older firmware or an older model?
Currently using one as I type, the stray / static finger rejection is near perfect and I can easily scroll with my index finger with my middle finger and edge of my palm resting on the surface.
You don't need to hold the non-clicking fingers over the mouse for longer time, just lift them slightly when clicking, so a click becomes one finger pressing down, the others slightly moving back in parallel.
Indeed, I never really had to develop a strategy, just started using it and used it since. Only thing I did was install magicprefs to make it slightly faster and never thought about the rest. Compared to the generic Microsoft-branded wireless mouse I used about 8 years ago with my PC, the difference is night and day. That mouse, designed for both left and right-handed people messed me up so much that my pink went numb for months even after I stopped using it. The magic mouse is much more comfortable than it looks, strangely enough.
