TLFTextField and AS3 / CS5

Question

Background:
I could not make a purely AS3 TextFlow object display text in the same way as a TLFTextField object in the library, even though the settings appeared to be the same (checked using the library xml file in the fla/zip). (The spacing between letters was not kerned in the same way.)
Therefore I changed tack and attempted to use a library object and update it with AS3. However, I feel that the TLF documentation is somewhat lacking, so I am sharing my findings, simple though they may seem to pros. The text was used for buttons, so I only needed to consider one paragraph with only one span.
What I worked out
It has taken me a long time, but I have finally worked out how to access the elements in a TLFTextField object in the library.
//create an instance of the 'tlfContainer' symbol containing the  TLFTextField object, with the Instance name 'tlfTextField' and 'default'  as the text.
var container:tlfContainer = new tlfContainer;
//target the textFlow of the object
var flow:TextFlow = container.tlfTextField.textFlow;
//get the first (and only) child of the TextFlow, which is a ParagraphElement
var paragraphElement:ParagraphElement = flow.getChildAt(0) as ParagraphElement;
//get the first (and only) child of the ParagraphElement, which is a SpanElement
var span:SpanElement = paragraphElement.getChildAt(0) as SpanElement;
Now I can change the text (eg span.text = "new text";) and format the text (eg paragraphElement.direction = "rtl") AND have it display correctly!
Questions:
1. Is something like this documented somewhere that I have missed?
2. Is there an easier way to do this, ie directly access elements? Using getParagraph() gave a null, even though the above worked..
3. Why should a dynamically generated TextFlow look different to a TLFTextField object?

Answer 1

It took me a while to find it when I saw an example of code a couple of days ago.
It basically means a variable number of comma delimited paramaters. From online doc's:
Statements, Keywords & Directives 
Definition keywords
... (rest) parameter
Specifies that a function will accept any number of comma-delimited arguments.
I am trying to find a coding example or two to model my own.
Thanks,
Jim