Just but it's faster to hit three F keys than wheel up for someone who is charging and power attacking against a prone opponent. To set this up I would have three hotkeys.
/die +2 charge <enter> and then drag to a function key
/die +1 power attack <enter> and then drag to a function key
/die +4 prone opponent <enter> and then drag to a function key (ok, yeah, the DM would really just adjust AC for that one but this is an example).
So, now if I wanted to power attack 2 points and charge that prone oppoent, it's f1+f2+f2+f3 and roll the d20.
It's just way faster.