If checking your privilege has become 'one of the great political rallying cries of 2013', we'd better all do it, right? And we'd better all do it right, right? Because to do it wrong wouldn't be much good. It's a thought that I'm familiar with from both professional and political experience. I remember a senior colleague once advising me that where you stand is where you sit, and I immediately grasped the point of his observation, running a large academic department as I then was and having preoccupations as a consequence that were novel to my old self and yet easily recognizable nonetheless to the new self I was becoming. Still, the anatomical difficulty of simultaneously standing where I sat did reinforce other thoughts I'd gleaned from the world of politics, and which, translated roughly, could be rendered so: you can't jump out of your own skin.
Well, you can't jump out of your skin, and that's the problem about checking your privilege. You ought to do this; but can you really? For we have two tendencies here of contrasting direction and unmeasurable relative power. Each of us is a grounded consciousness and disposed to see the world from the angle that this gives; at the same time, we need to check our privilege in order to make sure that we aren't overlooking advantages we possess that might obscure the difficulties of others.
Marxism has had endless experience with the variations. If you're a bourgeois intellectual, or even just bourgeois tout court, what can you bring to the struggles engaged in by working people for better lives? You can bring resources of knowledge possibly, acquired through your advantages. But beware lest you also bring habits of arrogance and superiority. You are not better than they are. The intellectual can only teach the masses [!] anything if she also knows how to learn from them. So the practices of knowledge and learning must be supplemented by practices of solidarity and action. From the dialectical interrelationship something good may come.
Yet, when all is said and done this means that even the privileged, blocked as they may initially be from seeing things true and clear, have the possibility of truth and clarity available to them if they try hard enough. And from among those whose struggle they aspire to help, from workers and other relatively disadvantaged people, agents of knowledge and political experience likewise emerge. Privilege or no privilege, we all have to do the best we can, trying to get things right - or, since people rarely get things altogether right, making a contribution to not getting them too badly wrong. So what comes out in the wash is the question itself that happens to be at issue and not the vantage points of the interlocutors. To put it baldly, a person of privilege may be able to give you a better argument against his particular privilege than someone who doesn't share it but would like to. And people without privilege are not always endowed with great wisdom, though, equally, people with much knowledge aren't always admirable in other ways, such as morally.
Then there is also the peril of not only thinking you know better than someone else - which it's possible that you might - but of being so certain about this that you claim a right to force it on them. You and the vanguard party. Your correct consciousness and the false consciousness of those poor benighted others. Go ahead, check your privilege on this one too: to think that by using a fashionable phrase you are revealed as a humble sort who has avoided the sin of not questioning the distortions in your own advantaged view of the world. But, of course, you may just be a one-person vanguard assuming you know better when you don't. And a smug lot, to boot.
My conclusion? Sit, stand, jump out of your skin - all you can do in this world is try your best to make sense of things.