Quote Poyser11="Poyser11"I think the issue was not whether it was deliberate/accidental or kick/no kick, but rather the fact that it went backwards off his leg, rather than forwards, before it touched the ground. If it had accidentally hit his leg and gone forwards, then that'd still be a knock on, nobody is debating that. But Cummins seemed pretty sure that the fact it hit his leg and went backwards meant that it wasn't a knock on.'"
No, you fundamentally misunderstand the rule.
Quote Poyser11KNOCK-ON means to knock the ball towards the opponents’ dead
ball line with hand or arm, while playing at the ball.'"
That is 100% certainly what he did.
Note: the definition
says NOTHING about the ball having to hit the ground, or an opponent. As soon as the ball is played forward, it has been knocked on.
What you are confusing is that
a knock on does not always stop play. You CAN knock on, but then retrieve the situation, so that play continues THIS DOES NOT MEAN YOU DIDN'T KNOCK ON, but it means the knock on will not lead to play being stopped.
If you accidentally knock on, but the regather, then it WAS still a knock on, but the rules let you off, and so it is play on. If you drop the ball forwards, but then kick it before it hits the ground, that was still a knock on, but you the rules say this allows play to go on.
Most people misunderstand this rule. They think that for it to be a knock on,the ball has to hit the ground or an opponent. But this is wrong. Hitting the ground or an opponent is what will
stop play. If you manage to avoid that by catching or kicking the ball, play will be allowed to continue, but it was still a knock on. Most people in conversation will say if you (for example, knock it forward but regather it), that "it wasn't a knock on". But it WAS. What they actually mean is, the knock on was cancelled out by managing to regather the ball.
Normally the distinction isn't important, but in this case it is crucial, because there are only 2 ways to negate the knock on, that would be to catch it, or kick it. He did neither. And therefore it remained a knock on which should have stopped play.