Being transparent, the Invisible Man would likely be blind. But more importantly, is it funnier to see the Invisible Man in full dress, or naked?
Are even the dark glasses too much? Would it be funnier with only the dog, and the caption, “The Invisible Man takes a walk.”
Mark Heath cartoons 
Full dress is definitely funnier without the caption :)
There’s a strong temptation to get rid of the clothes because it seems like a brave thing to do; erasing art, for the sake of the joke.