What is the real story here. Putting aside the theoretical statements and looking at what has in effect happened in hermeneutics you see that the principle of contempory conventions has been the real hermeneutic in the last 2,000 years. The western world, to a man, when speaking of the 'new testament' means the collection of writting of the deciples of the Christ. The context in which Jeremiah defined the words Brit Chadasha or new covenant has been superceded. So the result is that when you lay out the text of Jeremiah's prophecy on the new covenant you get jibberish. Try a test. Take the passage and write over the words 'new covenant' the words 'collection of writtings'. Read it aloud. Replace the word covenant with writtings as well. Read it aloud and listen to what you are saying.