[AS3] Embedding multiple members of a font-family

how/why is using

[AS][Embed(source="…/fonts/Verdana_Bold_Italic.ttf", fontWeight=“bold”, fontStyle=“italic”, fontName=“Verdana”, mimeType=“application/x-font-truetype”)]
public static const VerdanaBoldItalicTTF:String;[/AS]

better than adding the font to the FLA library and assigning the Font’s link, then declaring it in the code like in this example

[AS]myFormat.font = myFont.fontName;[/AS] (myFont being the embedded font, taken from http://www.adobe.com/devnet/flash/quickstart/embedding_fonts/#section1)