Standing under a high ball and running back with the flight are the bravest acts in footy. They are brave because you get smashed-it's inevitable. You can't really penalise somebody for something that can't be avoided.
Yeah, it's harsh on Greene. As Jazz says, the other bloke must bear responsibility for putting himself in harm's way. Remember this incident:
This kind of stuff used to happen semi-regularly, maybe not to the extent that Lewis was ko'd, but the foolhardiness of running back without looking was lauded as courageous, and anyone who looked or pulled out was derided as a squib. I think that attitude's changing, as it should. No one wants to see this.
Have a look. Look after yourself. It's not cowardice, it's self-preservation. Use your brain, to look after it.