Could some of them just be really rushed signatures? You know like Nolan was talking on his cell phone while exiting the hotel and was surrounded by 50 autograph hounds and he was just trying to sign as many as he could before he boarded the team bus? Or perhaps he was signing through a chain link fence, while some 14 year old kid held the card for him nervously?
Just a thought. I had PSA fail 3 Wayne Gretzky autos for me a few years back, autos that i got in person back in the early 90s. I got the autos in similar fashion to the incident i described above. Gretzky was playing for the Los Angeles Kings back in the early 90s and the Kings were one of the most popular teams to "Hound" back then up here in Calgary, Canada (I was a big autograph hound in my teenage years). Literally, almost 100 auto seekers would stand out in front of the team Hotel and try to get the players to sign as they exited the hotel and had to walk about 150 feet to the front street were the team bus was parked. Well as soon as Gretzky would walk out, there would literally be a "mosh pit" around him and he would just start signing autographs like crazy as he continued walking to the team bus. None of them really looked liked the autos that he would sign in paid, sit down signings, but nevertheless the autographs were still authentic Gretzky signatures.
Heres one of the Gretzky autos that i had signed right in front of me, that PSA failed..
So im not saying the Nolan Ryan's above are real or fake because honestly i do not know, im just saying that with autograph authentication, there are just so many variable factors that can effect the signature while its being signed, that you just gotta know PSA (or any company really) has to make many mistakes against real autos and for forgery's as well.