I agree it has so much to do with the audience you are targeting. But I don't think you have to ignore the guidelines and write dull text.
I remembered reading an article by Karon Thackston (a web copy writer) that was a before and after on a travel site.
It's a little old now, but I found a reference to that article.
Making an Emotional Connection
I think it takes a skilled writer to do this, but it's optimized text and well-written text can be combined.