This sort of ignorant BS is part of the problem.
It's along the same lines of 'they're a celebrity, they should be able to cop a bit of abuse on the chin. It's part of the job'.
Bullshit it is.
I hope this lowlife merkin gets outed and does some time for it. Then everyone else will realise they can't get away with it under a pseudonym or any other way. Farah, and anyone else, should be able to have a Twitter account to communicate with the decent part of the public without dealing with gutless people like the one involved here.
Be a decent person. Anything you write on here, or on Twitter etc should be something you're prepared to say to a person's face. That should be the basis for any human interaction. Too many people nowadays use the internet as a platform for bravado. Hell, half the posts on here wouldn't be expressed face-to-face.