You want to figure out why something in Flex or Rails works the way it does. For instance, how does all this data binding and active record association magic work?
Look at the source!
You’re wary of magic. On the other hand, take an SQL-select statement: now there’s something you can understand. It does what it says, and returns a result you can manage. Setting a variable to a new value; nothing magic there—you change the variable and it has a new value. Nothing else did it for you; you took action and manipulated it yourself, and now it has a new value.
Flex makes things easy and declarative. You have an XML tag that describes what you want to see, like a List ...