Well, @jobara i am using the "expandingAdjusters" grade while Alex has been using the conditional panels for the more/less functionality. We have discussed the reason for this in the past. As for the small duplicate pieces, i see that Alex is hooked to "onDomBind" event while, i'm hooked to "afterRender" event. Also, Alex refers to a "visualAlternativesMoreLess" DOM element while i refer to a "preferenceSwitchExpanding" element in the invoker. Some of these problems could be overcome but i thought i should not engineer this any further since, eventually, we will be using a unified, reusable way for more/less functionality, either refine the "expandingAdjusters" grade or resolve http://issues.fluidproject.org/browse/FLUID-5240. Or, even further, have you heard about the "< details >" and "< summary >" tags of HTML5?
http://www.w3schools.com/tags/tag_details.asp
http://www.w3schools.com/tags/tag_summary.asp
It doesn't have wide support yet though...