The EGR doesn't rob any power. I don't understand where that idea came from. At idle and WOT the EGR system is off and not doing anything to the engine. The EGR only works during part throttle cruising by pumping inert gases into the engine.
The problem with the resistor that fools the EGR is that it tricks the EEC into thinking the EGR is working properly when it isn't. As a result, at part throttle the computer leans out the mixture to compensate for the inert gases in the system. Without the EGR working, normal air is replacing the inert air and the engine will run slightly lean.
This isn't a prob at WOT, but you don't drive around at WOT all the time, so when you are just out cruising around, you would be running slightly lean which may cause probs.
The RIGHT way to remove the EGR requires burning a custom chip to modify the fuel curves at part throttle. If you aren't willing to go this far then you might as well leave the EGR functional because you are actually hurting performance rather than helping it