Thanks Simon.

I guess if grunt server doesn't work you could maybe use something like live preview (which is particularly well integrated with the Brackets code editor) or live reload (http://livereload.com/). In terms of quickly compiling from LESS to CSS I'm also a big fan of CodeKit (https://incident57.com/codekit/) on the Mac -- though there are various PC equivalents too (e.g. https://prepros.io/). 

So far as moving between the authoring tool and the framework is concerned, for me it's more about the relative convenience of getting a lot of content across into the right JSON format/structure, especially when working with team members who are much more comfortable with a CMS. I'd love to be able to get all the content roughly in place via the authoring tool, then dump that out in a way I could drop into a framework project for styling, incorporating plug-ins that don't work well with the authoring tool, and so on.

 I'd be interested to know how those working with the framework are handling the general data-entry. Just by copying and setting up by hand into JSON? Or have people got scripts/processes for quickly converting across from source documents?