If the 3rd frame is where DV first sees Windham coming, you know LESS than a second later they've made contact. DV is hard on the gas coming out of the turn, all he's probably thinking about at this point is the next turn, not wondering who's going to jump the track to take him out. I doubt anyone's reaction times are quick enough to divert their concentration, chop throttle, pull in the clutch, and hit the brakes in that time frame. It was a take out move. They were told before the race that type of behavior wouldn't be tolerated, he took a chance, it didn't work out. Bummer.
AX is a different animal altogether. I don't think the rule could be applied successfully..due to track size limitations and # of riders racing at once. But, the speeds aren't near as great either....so the possibility of inflicting injury is less.
DV's pass was definitely rubbing, but not an overly dangerous move. KW's was blatant. I agree, rubbing is racing, but you've got to draw the line somewhere. At this pace and without enforcement of the rules, by the time TP comes back to SX, he'll be no-footed can-caning people off their bikes on the triple!