You made an assertion but gave no facts.  You provided not a scintilla of supportive evidence for such a sweeping statement.  

Moreover, you act as if grace doesn't build on nature.  That's false teaching. 

Of course, God gave us an intellect for a reason.  And of course He gave us a free will to use well:   Both help us to come to know Him and His will more closely, and convincingly (and intimately, in a reason sense 'partaking' in His very will). 

Grace operating on a well-developed intellect (filled out with teaching from Scripture and the Church), and operating on the well-disposed will of a priest do far more good for God than your caricature of a theology-free vessel "fueled" by the Holy Spirit.  

It's a silly position to take.