I'd be inclined to agree with this. After all, how often do we make love in the dark, blindfolded etc... Removing sight is something we do anyway, to heighten the sexual experience, so its loss during sex would not be that great, quite the contrary, in fact.

I was initially going to choose to lose smell, but still having the scent of my own cum on me from a few hours ago, and knowing how it's making me feel, I'll go with losing sight if I had to choose.