The ActionController base class declares a lot of instance variables inside of each controller. During debugging, all
this "noise" can make it hard to find the instance variables that you are most interested in under the "self" node in
the local variables pane. The variables of most interest are usually those that you have set within your actions, in the
current class (as opposed to all those contributed by modules included by the parent class). Having to open up the
"self" node, and then search through an alphabetical listing, is tedious.

I have found that I rarely look under the "self" node; instead, I add the instance variables that I want to observe to
my watch list.

The code-completion dialog prioritizes items. So for a model instance, for example, I see at the top of the dialog the
fields that I defined in the model's migration. Would it make sense to apply some kind of sorting heuristic to instance
variables under the "self" node in the local variables pane of the debugging window?