In addition to revealing a linear order, a constituent structure tree has a hierarchical structure that  groups words into structural constituents shows the syntactic category of each structural  constituent, consequently is believed to most truthfully illustrate constituenrelationship  among linguistic elements.  
For example, the phrase " the old men women" may have two interpretations, i.e.the  adjective "old”may modify the noun "men", or the following two nouns "men women".Linear  order analysis cannot tell this difference, so it is ambiguous.Whereas,the constituent or tree  diagrams analysis can make this difference clear.So,we say tree diagrams are more advantageous  informative than linear structure analysis.  
The old men the women the old men the old women