Arg did some math then reread it and it's for assault spec. doh!
It shouldn't be too different for other specs, since you only have to know what percentage of your attacks is techbased (DoT's, shockstrike, Ion pulse are Tech based and hammershot and High Impact Bolt are Ranged based)
So if you find another percentage, say 60%, you multiply instead with ,071 with ,60. Then you will get a different, but similar spreadsheet and you can check wether cunning would be efficient. If the total amount of cunning and aim would exceed 2600, you would likely to come in conflict with Power, since power has a softspot around that amount of Aim.