Selecting all text and change kerning to optics - Indesign CS6

I have been trying set up a script that will select all the text in the open document and change the kerning to optical. or even a script the will change the kerning in the style sheet to optical. Either one would be great

this should get you started

tell application "Adobe InDesign CS6"
	activate
	set aDoc to active document
	tell aDoc
		set myText to object reference of paragraph 1 of story 1
		set applied font of myText to "Helvetica"
		set font style of myText to "Bold"
		set point size of myText to 10
		set kerning method of myText to "Optical"
	end tell
end tell