Basic overview and equations:
The sensitivity curve is a function of mouse input velocity against a value by which input is multiplied. This value is calculated as the ratio between output and input.
[outputx, outputy] = [inputx, inputy]*somefunction(sqrt(inputx^2+inputy^2)/time)
acceleratedsensitivity = sensmultiplier(1+accel*sensmultiplier(inputvelocity))
outputvelocity = acceleratedsensitivity*inputvelocity
Metho