I read the slate article just yesterday, the latest diagnosis doesn't sound well supported, and as if it's just a duplicate of issues from other somewhat established diagnoses.
I certainly have an intense 6 year old and at age 4 really really pondered whether help was warranted. But otoh in school she was pretty ok, so that always tipped us to the side of wait and see.
We've seen a slow but ever hopeful shift towards logic and reason and she is on less of a hair trigger.
Probably we are getting better at dealing, seeing things coming to a head and redirecting, etc.
I think one of the key factors in diagnosing a psychiatric disorder always has to be - are these symptoms/issues seen in MULTIPLE areas of their life? Home, school, sports, etc. I don't think it's possible to "power through" a mental illness all day at school, or, all night at home. I might be possible to avoid any symptoms during a 1hr soccer practice, but if practice is twice a week, every week for 12 weeks, you're bound to see the issues pop up then as well.
That was definitely the key in us seeking help with our son - we were seeing issues ALL THE TIME. In every setting!