FWIW, this is the position that Hollis Thomas is taking and is being backed by THE DOCTOR THAT PRESCRIBED HIS MEDICATION:
Amoss prescribed Thomas' asthma medication during training camp and wrote a letter outlining the drugs that Thomas was using for Thomas' appeal. Amoss indicated in the letter that the combination of drugs that Thomas was using, and continues to use, could result in a false positive test for clenbuterol.
http://www.nola.com/saints/t-p/index.ssf?/base/sports-2/1165479427162360.xml&coll=1
The NFL is saying that Thomas is being suspended for having clenbuterol in his system. If it is true that Thomas' medication could have caused a false positive for clenbuterol (I have no idea if it could or couldn't), then perhaps the NFL needs to look at this again. The NFL's statement to the NYT doesn't even address the possibility of a false positive. Personally, I would like to hear from some experts in the field of toxicology and get their take on whether it was possible that Thomas' medications could have caused a false positive. If they say it couldn't, then suspend him. If they say it could have caused a false positive, I don't see how the league can suspend him in good faith.