Ok, I completely understand your point, but even healthy adults have trouble walking the 5-6 + miles a day Disney requires to see and do. Many children his age ride in a stroller around Disney. I've seen 10-12 year olds in them. Disney doesn't have to do more than suggest that you keep his walking/standing to a minimum and that's the solution. I'm sorry.
I agree with Forevryoung.
If you
look at using a wheelchair or a stroller as 'crushing his spirit', it will do that.
If you look at it as a helpful tool to conserve energy, it will be that.
I know a number of people with CP who walked and looked at getting a wheelchair as a totally negative thing, to be avoided at all cost. Some of them ended up with problems later (arthritis in joints from overuse) that could have been avoided if they had made judicious use of a wheelchair. Some of them
were crushed to start using a wheelchair, because they had always looked at it as 'giving up' instead of just another tool (like some people wear glasses, some people use wheelchairs).
My DD has always had a wheelchair, but also used a walker and did walk around the house and short distances with her walker. She never
looked too good using it, but she got around.
She had a gait study when she was about 8 and the results of that showed she was using about
4 times as much energy to walk a certain distance as someone who didn't have CP would use. She stopped using the walker entirely after that point because she was starting to get arthritis in her wrists and knees (plus she developed seizures soon after and just was not safe in the walker). If she had been walking better, she would probably be still using a combination of walker/wheelchair, but it gives her much more independence to be a full time wheelchair user. I know other people with CP and post-polio syndrome who don't use a wheelchair in their daily life, but do for activities (like WDW or s afull day of shopping) that cause them to expend more energy.
Because your DS has CP, he's going to be expending even more energy to get from one place to another than other kids his age. And, as Forevryoung pointed out, many kids his age use strollers even though they don't have CP, so he will not be the only child his age using a stroller.
One thing a lot of people with endurance issues do is get a stroller or wheelchair and use it to get to a specific part of the park (like Fantasyland). They park it soon after the enter the area and then walk around and walk in lines. When they have made the 'circle' of the area and gotten back to the wheelchair/stroller, they use it to get to the next area where they repeat the process.
The amount of time and distance spend just walking around the parks is much more than you will spend in lines. That's why WDW suggests using a wheelchair/stroller/
ECv for people with endurance issues. If you have limited energy to spend, it makes more sense to conserve it for fun things than to use it all up just getting around.