Personally, it him it is the theory of mind-blindness that should be the ultimate test, not a collection of traits, and I do not think that parents should be forced to push for a premature, possibly inaccurate diagnosis simply to get their children services that schools or insurance might otherwise be unwilling to provide even though the functional impairment is clearly there.
In US, theoretically, it should be possible for schools to provide services based on functional needs but in practice, at least in my experiences, things don't move quickly unless there is a diagnosis. If I thought my DD needed services, I would rather go through our insurance so we can choose providers.
