<img src="http://dl.dropbox.com/u/939828/idea29.PNG">
Basically that could be displayed a lot nicer but to explain the concept...
I would hope it could be displayed a lot nicer, because in all honesty that hurts my brain more to look at than "clamp(distance(x1, y1, x2, y2,) * 3, 0, 100)"
And I think that's heading into the argument here about visual data flow. It's a nice idea for small, contained things, but once you get into more complicated stuff it's just a nightmare to look at. As you stated in your post things like lerp() and distance() are already taking long, complicated math problems and boiling them down into easier-to-handle chunks. If you start boiling things down much further you're going to swing the balance from "complicated abstract concept" over to "complicated practical implementation." In my opinion Construct is a rather comfortable middle-ground between the two. Yes, you still need to deal with some abstractions, but the trade off is the structure is easier to handle - rather than connecting potentially dozens of little dataflow boxes in a diagram to perform a math function you instead simply type in a couple of expressions. Those boxes may be easier for someone who is unwilling or incapable of learning to better visualize what's going on, but for those who put in the minimal effort of mastering the relatively simple math it would be too frustrating to work with.
Let's assume that each of those boxes and connections requires two clicks to create: A right-click to pop up a menu and a click to select what option you want...
Right Click -> Insert -> Math -> Click to select Distance evaluation component from menu
You navigate the menu and pick your component. Then you need to define the parameters:
Click Distance component -> Select Parameter A -> Click -> Navigate to Mouse Object -> Click
Click Distance component -> Select Parameter B -> Click -> Navigate to Player Object -> Click
Right Click -> Insert -> Math -> Click to select Multiply component from menu
Click Multiply widget -> Type "3" -> Hit Enter
Click & Drag connection from Distance component to Multiply component
Etc. etc. And that's only half the steps necessary to complete the equation. Not to mention moving the boxes around so you can see them easier when the view gets cluttered and you can't easily see your connections to figure out why your game isn't behaving the way it should be.
It's an unnecessarily bloated system when the alternative is to simply type "clamp(distance(x1, y1, x2, y2) * 3, 0, 100)" into the expression editor. If I had to click and create flow-chart boxes in Construct to perform simple math functions I would just use another program, because it would be way too much of a hassle to deal with.