I didn't read the article but here is a very brief explanation of those terms. On power push means that you have the throttle pulled and are giving power to the tires while attempting to turn. Its pushing because the front tires are not gripping. The rear tires have more traction than the front. You need to let off the throttle to cause weight to transfer to the front so that the car will rotate thru the turn.
Loose on power simply means that when giving throttle and attempting to turn the front maintains grip and the rear end looses traction and rotates around. Less skilled drivers will probably not be able to control this setup. But for skilled drivers this setup is faster. Its easier to control a car that is setup to push.
I hope this helps.