it 's always disappointing when a documentary fails to live up to -- or offer any new insight into -- its chosen topic . 
(ROOT (S (NP (NP (PRP it))) (VP (VBZ 's) (ADVP (RB always)) (ADJP (JJ disappointing)) (SBAR (WHADVP (WRB when)) (S (NP (DT a) (NN documentary)) (VP (VBZ fails) (S (VP (TO to) (VP (VP (VB live) (PRT (RP up)) (PP (IN to))) (, --) (CC or) (VP (VB offer) (NP (NP (DT any) (JJ new) (NN insight)) (PP (IN into)))) (, --) (NP (PRP$ its) (VBN chosen) (NN topic))))))))) (. .)))
(ROOT (S (NP (NP (PRP ))) (VP (VBZ ) (ADVP (RB )) (ADJP (JJ )) (SBAR (WHADVP (WRB )) (S (NP (DT ) (NN )) (VP (VBZ ) (S (VP (TO ) (VP (VP (VB ) (PRT (RP )) (PP (IN ))) (, ) (CC ) (VP (VB ) (NP (NP (DT ) (JJ ) (NN )) (PP (IN )))) (, ) (NP (PRP$ ) (VBN ) (NN ))))))))) (. )))