Those classified as on the 'upper end' of the spectrum may be less apt to seek an official diagnosis due to the potential for stigma. Parents of low-functioning children want an autism diagnosis as it allows for services in schools and some insurance coverage for therapies outside school.
The parent of a high-functioning child may only want a diagnosis when the child nears adulthood, in order to get adult services.
Many of those diagnosed are indeed 'fine', and some might be almost unrecognizable as autistic to an untrained eye. Once you've been around children with autism for a long time, you understand which traits reveal their condition.
Long sessions of social interaction aren't likely to happen unless they are forced. Kids in classes are given several breaks a day, and might start at periods of 1-2 minutes without a break and build to 10-15 minutes without a break.
The parent of a high-functioning child may only want a diagnosis when the child nears adulthood, in order to get adult services.
Many of those diagnosed are indeed 'fine', and some might be almost unrecognizable as autistic to an untrained eye. Once you've been around children with autism for a long time, you understand which traits reveal their condition.
Long sessions of social interaction aren't likely to happen unless they are forced. Kids in classes are given several breaks a day, and might start at periods of 1-2 minutes without a break and build to 10-15 minutes without a break.