I'm not quite sure what problem is this solving. What exactly does dataflow programming allow me to do that is not possible with non-data flow programming? It appears that the single components are still text, and data flow is only used to hook up these components. So how is this different than say an IDE with definition and reference lookup?

I've used Pure Data (which they mention) a little bit and here is an example of a somewhat advanced program. http://i.imgur.com/NRtG8Ai.jpg [1]. For Pure Data, dataflow somewhat makes sense (considering the problem domain) but if I had to pick between debugging the schema above and debugging text code, I think that I'd choose the latter.

[1] Image is from here http://www.spazioclang.org/eventi/live-electronics-con-pure-...

EDIT: Lol, here's an example of another PD program I found. http://i.imgur.com/Flwviol.jpg Now imagine that you inherit a legacy codebase that looks like that.