Link to original page on YouTube.
Some things I think he could have done differently to avoid that situation:
1. I think his speed was too fast for those conditions. It's foreseeable that there could be pedestrians around or cars suddenly pulling out.
Failing that...
2. He witnessed the first child run out far ahead of him. He should have then immediately reduced his speed to account for the eventuality that more children would run out (a reasonable assumption).
Failing that...
3. A child is now running out on a collision course with him. He had very little time to react. The optimal decision I can see would have been to hard steer away from the child towards his right and then applied hard braking. To be able to do this, you have to be practised at emergency hard steering. You need to have programmed it into your body.
Videos always make it hard to judge distance and speed. If there in-fact was no time and space to steer away, I always fall back on emergency braking so the impact force of a collision is reduced. I shave off as much speed as possible as quick as possible. Again this requires that you are well practised at braking and your brakes are properly maintained. You can improve upon the situation by always having your front brake lever covered. However, it's essential that you have trained yourself not to suddenly snap the brake lever closed when you need to stop quickly.