I thought as soon as the team that knocked on touched the ball again after the initial knock on, play was then stopped?

I never looked at it like that Keith. I just looked at it as a mistake but you are right. You only have to look at Ben Crooks try.

Free play, love the idea of this, they don't use it in the NRL

Free play, love the idea of this, they don't use it in the NRL, they trialled in the NRL 9's in February and a lot of players got confused. I know its old hat in the UK
but in slippy conditions and a ball bobbling about with attackers hunting you down you don't take chances. Hence the reason that some in goal defenders don't take chances better to back your defence than try and be the superstar and gift the opposition a try .... ala Crooks

Fact it was a free play was irrelevant, getting possession of the ball would always be preferable but sometimes have to play it safe.