RE: How would you re-write this code to hide/show content

You can also use a live callback like this

        renderContentOn: html
                html 
                        selectFromList: #(1 2 3) 
                        selected: #'1' 
                        callback: [:v | ] 
                        labels: [:ea | ea asString]
                        liveCallback:
                                [:item :h |
                                h spanNamed: 'selection' with: [ self 
renderDiv: item on: h ]].
                html break.
                html spanNamed: 'selection' with: ''.

        renderDiv: divNumber on: html
                self perform: ('renderDiv' , divNumber asString , 'On:') 
asSymbol with: html.

        renderDiv1On: html
                html divNamed: 'div1' with: 'div1 contents'.

(this also uses some Javascript, see liveUpdate in WAStandardScripts)
Enjoy,
Michel.