It's The Ashes (again)

[SuperBob2002]

I’ve watched the smith catch to dismiss Root a dozen times and I don’t know what the video saw but the ball definitely touches the ground it should have been not out. Just like the green Duckett in the first test.
For me unless they can be absolutely sure it should be not out. There guessing wrong
Just my unbiased opinion of course.

Good post. It wasn't a catch. If you pause it at the right spot the ball makes contact with the grass. 

The fact the third umpire had to have several looks at it tells me he wasn't sure, therefore it's not out - you shouldn't give a wicket unless you're 100% sure it's out.