"If you get a black belt at Fusion, you know you deserve it," says Con. "I'll always choose the hard-worker over the person with talent who hasn't put in."
"The only time I had doubts was during the kicking routines," said Connie later. "With everyone watching and going so fast, there was no time to catch my breath."
The grading has been going for an hour - only three more to go.
Next, students are asked to demonstrate one-step sparring routines in pairs. They are a series of set movements combining blocks, kicks, punches and self-defence moves to defend against an opponent.
But the sparring, or free-form combat sessions means the time has come to be reminded that Taekwondo is a contact sport.
There's no holding back in the full contact rounds, and the whack of a foot connecting can be heard over the shouting. Without protective gear, the sound of every strike signals pain.
A student thinks he'll outsmart an opponent by holding his leg. Instead he gets kicked in the jaw with a move that's straight out of a martial arts movie. The kick is strong enough to have caused serious damage, and for a moment proceedings stop to check he can continue.
After another short break the students demonstrate Taekwondo patterns (poomsae). There can be as many as twenty-five steps in the more complicated ones - each must be executed with precision and power. If students have trained solidly over the years it helps; now that they are close to exhaustion, they need to rely on muscle memory.
Self-defence is the most likely ingredient of Taekwondo training to be used in a real life situation. In pairs, students show a handful of moves to defend against a physical and weapon attack. To the spectators, it looks impressive, but it's no fun for the attacker who is often thrown to ground or subdued in a painful lock.
The mood in the room seems more relaxed now, even playful. The group of students know the worst is over. It's not finished though; students are asked to stand in front of the head instructors and explain a designated pattern. It doesn't sound too hard, but it must be done in Korean.
A black-belt grading wouldn't be complete without board-breaking. With the correct technique, the pine boards break easily, but you can never be sure with a spinning or aerial kick, and it's been three hours since the grading started: the group is spent.