By all means, anyone who is even considering getting a GAC, don't consider it, just get it.
firstly, you don't have to "apply" for the pass, simply visit Guest Relations and ask for a GAC. They'll ask what you need it for...they're not questioning the validity of your concern, but rather, what assistance you will require. When I got my last one a few weeks ago, I just barely started to tell the CM what I needed it for and he was already pulling out the appropriate GAC. The Guest Relations CMs are all pretty good, and they've probably heard it all before so will probably be able to steer you towards the correct GAC that you need.
One I had it, I'd say 8 out of 10 times the CM would see me holding the red card in my hand, and before I had a chance to say hello was greeting me and pointing me in the right direction. I had one fabulous CM at the Snow White ride describing to me exactly what I SHOULD be seeing (I'm mostly blind), what the cars I'm riding in look like, what is in the ride and who's mine car we were riding in (he had us wait for Dopey, as that was his fave, and it was coming up). I didn't have the heart to tell the guy we had been several times before, he seemed to have such a good time helping us
Those times when the CMs actually read the GAC, they saw what help I needed and then were able to point me in the right direction. I've only once had a bad experience with having a GAC, and that was with a CM at the head of the Maelstrom ride in Norway tell me the GAC I had wasn't the one I needed, as the one I had was to get me in the wheelchair entrance, and since I didn't have a wheelchair, it was the wrong one. I was tired and didn't feel like explaining to the CM that the GAC was specifically for people NOT in wheelchairs/ECVs...but he was young, probably new, the last attraction we were going to, so I let it slide.
At any rate, GACs make life so much easier, definatly go and get one!
Tim