Agree with all your points, but have to say that used is used and no one can detect a warped record in a sealed package, new or old. Case in point - just bought Chick Corea's The Vigil. New, 2013 release, 2013 pressing, supposedly audiophile grade vinyl. Warped right out of the package. I got lucky because it sounds great, but getting the VTA right was a challenge. Similar issue with David Byrne's and Saint Vincent's duet, also new. Warped records are a big reason why vinyl is mostly a geek preserve today. That said, just picked up a 180 gram re-issue of Stanley Clarke's School Days and it's perfect.
On used stuff, got a couple of old Sheffields here a year or so ago, and one had a totally trashed first track 1 without any visual clue at all. The remainder was just fine. Pulled out a couple of really old pressings from when I was a child for comparison, and they were still playable, if not great. I could hear the damage done by my sister's old GE portable record changer (tube driven, btw), but it was better than track 1 on the damaged Sheffield.
IMO, a uniform grading system is better than nothing, but caveat emptor remains the law of the land.
On used stuff, got a couple of old Sheffields here a year or so ago, and one had a totally trashed first track 1 without any visual clue at all. The remainder was just fine. Pulled out a couple of really old pressings from when I was a child for comparison, and they were still playable, if not great. I could hear the damage done by my sister's old GE portable record changer (tube driven, btw), but it was better than track 1 on the damaged Sheffield.
IMO, a uniform grading system is better than nothing, but caveat emptor remains the law of the land.