While I am a fast SQL writer, having to munge and navigate the multiple relation tables during our fast-paced discussion was a little unwieldy. A tool like this to quickly jump between joins and look at the result sets while in the midst of a technical discussion as it evolves would have been perfect.
The coding space is big, permitting lots of invalid state -- most of the programs you could write are not just wrong but gibberish. Using a GUI like this reduces the problem space enormously; the comparison feels akin to the one between grabbing a live fish and connecting Lego blocks.