4eyed, your comments are indeed insensitive, however I believe they are made more out of ignorance than a desire to be mean. It is clear that you do not have a full understanding of the ADHD/ADD diagnosis. I can relate to this lack of understanding, as I too was not fully educated about this dx until I adopted my DD who has ADHD (and this was despite being a teacher for many years who taught ADD students and had done some research on the disorder!)
It is correct that their are many levels of ADD with corresponding conditions/behaviors. My neighbor's daughter, for example, has ADD and "waiting" has never been an issue for her. Thus, a GAC card would be inappropriate for her. She has completely different issues than my DD, yet they share the same dx.
You seem to understand that a GAC is necessary for some conditions, vision, mental issues, etc. However, you seem to not understand that ADD IS a neurological condition. It is not something that a person can control. A child can use a varity of interventions to help with ADD (changes in diet, medication, behavior modification, social training, etc..) that may help with the ADD, however it is not turned on and off by will power. The ability to "control" the effects of ADD is greatly affected by the severity of the ADD.
Many children with ADD have other condition that effect their behavior. My DD, for example, has sensory integration issues (which, again, compound her difficulty with being in close quarters, standing close to others for long periods of time). These conditions are complex, and should not be mistaken for lack of will power, laziness, or being given a sense of entitlement by a parent because of their disability.
The GAC has proven invaluable for our family. We do not simply go to the front of the line. We are often provided with a more secluded, quiet area to wait for a ride or a show. We are also allowed to use a stroller as a wheelchair to continue through a line. This greatly helps our DD and makes a trip to Disney doable. Without the GAC, my daughter's experiences (thus our family's experiences) would be severely limited.
We do not ask for a GAC card because we think our time is more valuable than another guest's time. We simply ask for an alternative to waiting in lines in the traditional sense. Again, we still wait but in an area better suited to meet the needs (not just desires) of our DD, and in a stroller as opposed to standing. I am also blessed with two sons who fortunately do not have any conditions that necessitate a GAC. They are expected to wait in lines just as anyone else does. Again, we do not view the GAC for our DD as a "front-of-the-line" pass, but as a means to an alternative method of waiting. We still wait for our turn.
I believe you mentioned that you have a son with ADD. I would highly recommend becoming involved with your local CHADD (Children and Adults with ADD) group if you have not already. Our group has provided me with a ton of information about the disorder and a much better understanding of the complexity of it. The national umbrella group has a wonderful website that lists many of the myths associated with ADD that I think it may dispel some of the beliefs you may hold regarding ADD. I know that it certainly helped me whan I began this journey with my DD.
I wish you the best of luck in your journey with your son.