Students ask Sifu to demonstrate black belt material on them and then experience a great shock because it was way more scary than they'd anticipated.
Here's a tip: it is in the black belt syllabus for a reason.
There are 10 belts before you take the first black belt grade.
This should tell you something...
Your body needs time to loosen, strengthen and be prepared for the experienced syllabus.
You need time to cultivate internal strength. You need to know how to fall safely.