Jammer Six... I hope you were kidding when you said shiny brass shot better. That' definately not true. It just looks better. I've been reloading for 39 years and have finally come to think that polishing cases is like putting make-up on a woman. It makes them look better but it doesn't do anything for their character. I've many sets of dies that have never had a cleaned case ran through them and they're not worn out as some think will happen if you don't clean your cases. I just make sure they're not dirty inside and wipe them off with a rag before running into the die.
Cleaning a case doesn't change their tolerances so I don't see how they'd make for more accurate loads. In fact, the top barrel makers will tell you that those who clean their cases religiously have more throat erosion than those who don't clean cases because of the abrasives they're blowing down their barrels.
Besides looking nice there's no advantage to cleaning cases. It's all hype and many fall for it. Look how much money people are making from this case cleaning business. I chose to invest my $$ in powder and lead.