I think he was making a comparison is all.....but I can answer your question. On a mild to moderate hot rodded engine, EGR can actually be beneficial. As long as there is vacuum enough to operate it correctly, it will still function as intended.
They cool the combustion process and can pick mileage up a little.....and they DO work, contrary to what some people say. If they are in good operating condition and have enough vacuum to operate, they will work pretty well.
Now, having said all that, I'll never go to the trouble to ADD one where one is not. lol