Using the <head> tag with template files (p. 284)
<!- TemplateBeginEditable name="head" -> <!- TemplateEndEditable ->
Template expressions and optional regions (p. 314)
<!- TemplateParam name= "needsAccessories" type = "boolean" value = "false">
and
<!- TemplateBeginIf cond="needsAccessories" ->
<!- TemplateEndIf ->
and
<!- TemplateBeginIf cond="needsAccessories && specialOffer" ->
<!- TemplateEndIf ->