There sure was a lot of cleaning back then.

I recently submitted three commemorative half dollars for grading. All three had been purchased at least 25 years ago when 3rd party grading didn't exist and Photograde was the best resource on the market. I believe all three were purchased by mail order although it has been too long to have a true recollection. The coins were an Oregon Trail, a Sesquicentennial, and a Grant. All three came back UNC Details/Improperly Cleaned.

I just sent, this past Friday, a Rhode Island and Arkansas halves, I hope they come back w/o details. On the plus side, I also sent in a Bay Bridge half I had acquired from a company in Colorado at least 30 years ago. At the time of my purchase, the coin came with a written certification stating the coin was AU. The Bay Bridge Half came back from NGC as AU55. That's a nice testament to the integrity of L and L coins.