So you think a "crazy test" will suffice---

I don't think so. They're is an old saying and it's very true--"crazy like a fox." There are many people in this country that can act--pass tests--and be as normal as your next door neighbor--and then go off and commit mass murder without anyone blinking an eye--and people who knew them are shocked that they were capable of doing what they did. It happens all of the time.
We have to ask ourselves--why we need assault weapons to be sold to the public today. They're certainly not for personal safety--unless you plan on getting attacked by 100's of people at once. If you're thinking about taking on the Federal Government with one--I'll remind you of their bombs and preditor drones.
The only purpose of an assault weapon is to kill people in mass. And that couldn't have been more clear as to what this elementary school teacher had purchased and registered in her own name--that her nutcase son obviously had complete access too.
Here it is- Bushmaster .223-with a 30 round clip--sells for around $650.00