In the offseason we hardly use it at all. When it becomes very crowded, we use it as needed. If there are long, touchy lines and no Fastpass, for example, we will use it. We use it at attractions that have FastPass, and depending on the CM there, they will sometimes tell us to go ahead without the ticket if it isn't too crowded. For example, if we are going to a show like Fantasmic and it is very crowded, we will ask to be seated in the accessible area (assuming there is enough room) because it is slightly roped off... if my son jumps up and starts flapping his arms there it isn't as disruptive to others, he isn't hitting anybody. And when my arthritis is flaring, nobody would know that but me, I need it for avoiding stairs, seating, that sort of thing, and when my kids are with me that goes double and beyond.
I flash it to get the closer parking spaces at the regular lot -- I could explain the need to the attendant without the GAC, but it takes about 7 seconds off the explanation time if I have the card. When I go to the First Aid station to clean up a mess (it still happens) they just kind of know right away when they see the card, there is just a nod of recognition and they let you in. I don't know quite how to explain it... it isn't that it is a pass, it is just a sign that you may need assistance, and they don't need a big explanation. I have done it both ways, with and without the card... it isn't always immediately obvious from looking at my son that he is autistic. Also, there have been a few times when we have had full-blown tantrums and very difficult scenes, and they have been very helpful in getting us off to a quiet waiting place off to the side to calm down, or have offered a hand cleaning up without making any scenes or causing any hard moments that would make things more difficult... Just having the GAC in the holder around my neck just takes the edge off the difficult moments. I flash it, they go, "Ahh... OK..." and they just go into help mode.
I have done it without the GAC a few times, when he was acting up, and again it is hard to explain to people who don't have special needs kids, but I just get more of "The Look" from CMs during those times when he flips out and I don't have the card... you know, "The Look"

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