Hey Marine- Someone in one of these threads recently said that the quality control at the Philly mint sucks. I believe it!
With millions and millions of these quarters being struck I doubt anyone in quality control will be inspecting these with a loupe or lens. Without an eye aid to magnify these coins, the chips and gouges aren't even noticed by 99% of those using them.
If I recall the last coin video that I watched of the coins coming out of the press into the basket they showed the inspector using a work magnifying light I have one on my workbench it's about 8 inches in diameter and has a circular bulb mine has about a 10 magnification and if I recall they had the same kind in the video inspector pulls a coin out of the been and looks at it under the magnifying glass one of those mint videos shows it but like you say with millions of coins I believe they only look at every four or 5000 or when ever the inspector decides to check the quality of the coins coming out of the press check out YouTube hope this could be some help