A simple page like that should be easier and faster to create from scratch using a WYSIWYG tool, and then publish to a web platform that support it.... than copying the source and then editing it in a text editor.
I know in the past such WYSIWYG tools were too rigid and thus we have a generation of designers that work in text.... but it just seems so archaic to me.
Like building images with text, rather than using photoshop.
I write code on the backend, that lives on servers, I don't write HTML for a living, so maybe I'm missing some necessary requirement that forces people to work in text editors.... but a straightforward page like that should be much faster to create by dragging a button element onto it, even a generic one and picking the image, and then putting text boxes in there and setting their style, etc, should take maybe 2 minutes if the assets are already created. Not being able to do so seems like such a time sync.
I remember once not too long ago tweaking a landing page, by going back and changing absolute pixel offsets 2-3 pixels at a time in text. I've done this with iOS code as well. Change the text, compile, run, how does it look? ok, need to go farther, back into the editor, bump it up 2 more pixels. etc.
FWIW, if anyone knows of visual tools from startups or open source that are trying to solve this problem, I'd be keen to hear about them. (I'm building a web platform, and rather than create my own design tool would rather support existing ones with my platform.)
The closest I'm aware of is Cappucino which supports using Apple's Interface Builder to layout UI for Webapps, and then export the IB files to the Cappucino format. Sproutcore had Greenhouse which looked even better, but seems to have been abandoned.
A better tool would mean easier AB testing, maybe even ABC testing... faster development and more iterative design. I see no reason that such a tool couldn't be made, or would have to necessarily impose restrictions that limited its functionality... and I think that boosting web designer productivity would be hugely valuable. On the other hand, I can't imagine why nobody has tackled this.
PS-- on the mac there's Flux, which sorta does this, but it doesn't integrate with a common web framework like rails, etc. I mean, you can, but it seems more suited to static pages. http://theescapers.com/flux/