I think you need to be careful that the plate you are using is CHROME plated and not Stainless Steel. I have used both and the Stainless Steel plates are prone to a whole host of problems in this application. You are quite right that the tiniest scratch on the plate will show up on the print. There is no polish or treatment that will fix this other than having the chromium plating replaced. If you are using a chrome plate that is really, REALLY clean, then place a soaked wet print, straight from the last wash, face down and roll it with a soft rubber brayer. The idea is to get the emulsion to FULLY contact the plate. Then use some paper towel to mop up the water from the back of the print, cover with a blotting layer, and apply an even weight. Let stand for at least 48 hours and then uncover. Allow the print to dry and 'release' on its own. All those polishes and 'release' fluids and all that crap are only required on stainless steel plates and they do not really work anyway. they cause more trouble than they are worth. The Arkay plates sold by B&H are the only chrome ones currently made that I know of. Also, they are the only ones big enough to do 16x20".
It is a great process because it will leave a glassy mirror-like shine on the surface of your print that is not attainable any other way. It also increases the DMax significantly (obvious effect of increasing gloss).