I don't know where our disconnect is here, sorry. I'm not saying anything remotely negative about A/B. I'm saying that despite business owners understanding the potential, other things get in the way (other projects, time constraints, etc). For many people, their website isn't their primary means of revenue and their designers' and copywriters' time is best spent on the part of the business where shareholders have proven results of their effectiveness and value-add.
if it does not make money how is there budget for professional designer and copywriters? Edit It's late, that post is more aggressive than I meant it to be and so, I apologise for snapping at you, I would like to suggest you have a look at @patio11's blog Kalzumeus if you want to be bludgeoned with AB test positivity, and bid you goodnight
But seriously, AB test your designs - in fact I might suggest that designers who offer a design-and-test service would make more cash and more leverage in negotiations than not
now there is an interesting counter to 99designs