As his next student steps up to the rolled tatami mat and squares their stance - their eyes fixed ahead, and the spotless katana blade angled forward - the Sensei checks their form. The student raises the blade and brings it down, embedding the edge into the mat.
"More left hand," the teacher says, in a gentle tone. "And relax. Look at the bamboo and not at the mat."
The student brings the blade down again and cuts clean through.
"That's it," the Sensei says.
Steven Bowden has practised taekwondo for years - he was an instructor at one time - but has taken up Aikido in the last few months. He trains two nights a week at the Newcastle Aikido dojo at Hamilton. Aikido is a lower-impact discipline than taekwondo, he says, but it places a higher demand on his focus. Cutting the tatami mats was the perfect example; success isn't about how hard you can hit the mat, rather it is the exacting technique that produces the cleanest cut.
"The movements are all precise," Mr Bowden says. "It's a real meditative state that you have to enter into. So, Aikido is good for the mind and the body, coordination, and strength."
At the suburban dojo on Bennett Street on Saturday morning, August 17, Sensei Darius Wingate-Pearse led his students through the katana exercise one by one and offered similar small guidance to each. The lesson began with a lengthy meditation in which the students squared themselves with the finality of the technique. As Mr Wingate-Pearse explained, you can't take a cut back.
"You can't undo it," he says. "There's no delete key or redo. Meditation makes us as clear as we can be in the moment.
"A lot of people use the term Zen in air quotes, but we actually practise it. The Samurai practised to get the noise out of their heads - if I'm worried about yesterday or tomorrow, then I can't focus enough on the now, and if you're trying to kill me with a sword, then now is really important."
In the internet age and self-motivating culture, the idea of living in the present has become somewhat quaint, but the practice can be demanding, the Sensei says.
"A lot of people talk about it, but they don't want to do the work," he says with a smile. "The most intense one that I have done was for eight days. Just sitting still. I wanted to die after about day four, but by day eight, it felt like I was in the Matrix."
The intense focus bleeds into the rigorous technique as the students settle into their stance and slowly raise the katana on their turn. Every movement is undertaken with a unique purpose and careful precision, from the placement of their feet through every joint to the arrangement of their hands on the Tsuka, the angle of their swing and finally, the rest.
"I must admit, when I picked up the sword, my heart skipped a beat. The adrenaline kicked in," Mr Bowden says. "You can visualise it all you want - and that is a part of it - but getting the kinetic feel of it, actually doing it ... in the heat of the moment, with everyone watching. It's a mixture of feelings up to a balance with immense satisfaction when you cut through."
In the moment, Mr Bowden takes a moment and gathers himself. His eyes are fixed ahead, his hands locked around the Tsuka, and his stance is wide and balanced. He falls back on his training and draws his focus into the microscopic edge of the blade.
The tatami mats are made from a woven straw soaked in water and rolled to - at least anecdotally - resemble the density and resistance of flesh. It's a macabre thought, but Mr Wingate-Pearse says the teaching isn't about violence but the philosophy of practice, discipline and focus.
"What I teach is really easy to do," he says. "But it's hard to remember when you need to do it. Everyone can be calm on the couch, but if someone is yelling at you in the street, then that is when you need to practice calm and focus and bring it to bear when you need it.
"Everyone thinks they can do a good job at this, but when it comes down to it, these students have a razor-sharp sword in their hand - there is a chance they will drop it, they could chip the sword on the ground or maybe even cut themselves. They have to walk the walk."
As Mr Bowden's blade passes cleanly through the tatami, swing after swing, he pauses for a moment before he steps back and hands the katana back to his instructor.
"This is the first time I have ever cut tatami," he says. "If you had told me 12 months ago that I would be doing this, I would have said 'yeah, right'. But all you can do is train, and this is where your training pays off."
