[rainforest]

> Now imagine that you inherit a legacy codebase that looks like that.

I wager that every codebase beyond a few years of churn looks like that, you just don't look at the CFG to see how much of a mess it is.

There's a key to their approach in that abstraction can be used - the nodes aren't statements as they are in PD, but chunks of code. This means the low-level stuff is hidden from you and you see how higher-level components integrate (if you take the time to tell it what the high level components are, presumably).