You realize, of course, that this idea that the connotation matters more than denotation is a "science" that, historically speaking, has generally been associated with the left: a association which, if I considered myself a leftist, I would find quite insulting. Those sorts of attitudes are a big part of what drove me away from the left in my late teens, in fact. (the rest was, well, mostly that I was making a lot of money; it's hard not to be a libertarian at 19; way more so when you are making lots of money.)

Barthes was an interesting writer, sure, and he brought up some interesting points, but like most leftists of his era, (ok, to be fair, just about everyone of his era.) he vastly underestimated the complexity of the human brain.

The problem with relying too heavily on semiotics is that it's pretty obvious; and it's really easy to sound like you are trying too hard to manipulate your audience; something most of us find pretty offensive. The other problem is that the connotation of a particular word varies quite a lot on the cultural background of the speaker; so while semiotics can work to whip up people who are like you and agree with you, it's unlikely to work well when speaking to a group of people from diverse backgrounds.