but that they are doing it is thought-provoking . 
(ROOT (S (CC but) (SBAR (IN that) (S (NP (PRP they)) (VP (VBP are) (VP (VBG doing) (NP (PRP it)))))) (VP (VBZ is) (ADJP (VBN thought) (HYPH -) (JJ provoking))) (. .)))
(ROOT (S (CC ) (SBAR (IN ) (S (NP (PRP )) (VP (VBP ) (VP (VBG ) (NP (PRP )))))) (VP (VBZ ) (ADJP (VBN ) (HYPH ) (JJ ))) (. )))