Actually, you're copying more than a git clone command.
That's the point of the posting.
Look at the source or paste into a text editor to see it.
i think gizmo686 is aware of that. what he says is that he trusted the source where he c&p's from.
if you don't trurst the source you should not blindly copy any command. Even one flag/parameter that you might not know can do harm. There do not have to be hidden characters to make it harmful and dangerous.
But do you trust the website, email, or other source, where you copied the command? If someone can spoof this link on the official kernel website, they may as well have access to other, way more sensitive resources.