Alright here is what I know.
Under the 1996 HIPPA Act, it is illegal for a company to know your medical history for the purpose of a job. Now many do have medicals, but how they have been administered has changed.
Previously airlines had access to the results and questioners that you answered during this exam. Now all they get is a yes or no from the medical professionals.
All of that stuff (color vision, irregular heart beat, etc is dealt with with the doctors or DO's that perform the exam) Now if you have a wavier, it is not on your medical as you are qualified with no restrictions due to the waiver from the letter. During the interview and your are not under a special issuance letter ( On your medical, in the restrictions box will state that it is not valid after six or 12 months depending on what it is for. Companies know this and look for that. It is a dead giveaway that you are under an SI) you do not need to disclose this. When you take your test with the health facility and do not pass, whip out this letter. It has been sufficient for plenty of people. I know of five people that had issues at DAL the last round and all of them had wavers and none of them disclosed anything except to the dr. There letters were more than sufficient.
This law really protects you. IMHO it is one of the best things that Clinton did.