that could so easily have been fumbled by a lesser filmmaker 
(ROOT (S (NP (DT that)) (VP (MD could) (ADVP (RB so) (RB easily)) (VP (VB have) (VP (VBN been) (VP (VBN fumbled) (PP (IN by) (NP (DT a) (JJR lesser) (NN filmmaker)))))))))
(ROOT (S (NP (DT )) (VP (MD ) (ADVP (RB ) (RB )) (VP (VB ) (VP (VBN ) (VP (VBN ) (PP (IN ) (NP (DT ) (JJR ) (NN )))))))))