I don't know about this. At my last job, one of the very first problems dropped in my lap was to fix a debugging tool that had been mostly written in Workflow Foundation, a flowchart-based programming environment for .NET that isn't domain-specific, esoteric, or intended for children. It was the tenth circle of Hell and almost drove me to a nervous breakdown in my first month on the job. Despite how often I quote Joel Spolsky's "never rewrite the project from scratch" essay, I threw the whole thing out and wrote it again, and was much better off for doing so.

Now, certainly the specific failings of WF, and the bast^H^H^H^H person who wrote the tool were partially to blame here, but even with all that in mind, the experience has permanently soured me on visual programming. It has all kinds of flaws-- it's harder to reason about, harder to debug, harder to comment, and harder to quickly modify that plain old source code. If there was some trade-off, an upside for all that trouble, maybe it would be worth it, but I can't see one.