[devonin]

It is generally assumed, going by the playstyles of -most- (but not all) of the top players, that "spread" is the optimal playstyle for playing at the higher level.

That is, any set of keybindings where you are using the index and middle finger of both hands for your four arrows. Things like ASKL or ASL; or AXML or whatever is most comfortable given the shape of your hand and length of your fingers.

That said, there are plenty of high-skill players who play Index (only index fingers) and even one-handed, but they do appear to be the exception statistically.