Cool - thanks for posting, even though it made me a bit seasick!
Completely OT:
That yellow marker in the barrel as the tank waltzed around close to the end reminded me of the story told of aligning a 9 kW CO2 laser - the coarse alignment begins with a piece of tape stuck to the laser nozzle, a shot is taken, and someone checks to see if the hole is close to the centre. This is repeated with adjustments made to the alignment. At one point the guy doing this noticed the tape coming off, and adjusted it with his finger at just the wrong moment.
At least the hole was nicely cauterized by the beam, no blood loss. Laser piercing really works.