Not particularly IMO. It's harder to see from the angle, but his back still looks fairly straight, and although it's always better to have a smooth lift from beginning to end, a lot of lifters will kinda hitch it up their legs at the final stage of a deadlift if the weight's at the very top of their range- I wouldn't call it bad technique when experts do it, though it's more impressive when they don't do it. An 18 year old lifting over 300kg is ridiculously impressive, and unless you're Ed Coan, the heavier lifts will never look as easy or look as good in form as the lighter lifts.
When I see people hitch the bar up at the end, I always think of Mariusz Pudzianowski:
http://youtu.be/Zrw-7Svq-7k?t=1m18s
I'm fairly sure they're against the rules in powerlifting meets, but they're allowed in Strongman. I'd definitely recommend against it though because it does increase the chance of an injury.
http://youtu.be/1FmwdTI8N1E?t=1m20s
This is great technique though. Super heavy weight with no hitching.
When I see people hitch the bar up at the end, I always think of Mariusz Pudzianowski:
http://youtu.be/Zrw-7Svq-7k?t=1m18s
I'm fairly sure they're against the rules in powerlifting meets, but they're allowed in Strongman. I'd definitely recommend against it though because it does increase the chance of an injury.
http://youtu.be/1FmwdTI8N1E?t=1m20s
This is great technique though. Super heavy weight with no hitching.