The only odd thing I appear to see about that Dean glitch is score placement. He wasn't awarded points for the first part of the barrel jump because he was too close, what he was awarded was catching the back side of the barrel after coming off the wall....similar to if you double jump a barrel on the same girder, the second jump is points against the backside of the barrel. Also, once bouncing off the wall things are not completely normal. But, it is an odd thing I never saw.
EDIT: Actually, tried every which way I could to jump a barrel like that to recreate that and no dice...even tried releasing controls in the air and repressing when landing. Still jump normal 100 pts for the first jump. That is crazy.