Please stop lecturing me on what to study and just answer my question. You have no idea how much time I spent on openings, tactics, strategy or the endgame. The opening is probably about 30% of the time I spent on studying chess.
Despite the greater importance of the other areas of chess, a good understanding of the opening is key to success. After all, knowing an opening well will give you important strategic insight, a familiar middle game and an idea of roughly how well you would do in the endgame as well as how to handle it. It is by no means to be ignored, even for 1600 players.
But in any case, I I'm probably closer to 1700 than 1600. This rating is provisional and based on my performance on FICS, USCL, ICC, Playchess.com, etc., I think it is not representative.
Anyway, back to the question, what line has worked best for you against the Najdotf? (For me it has been 1. e4 c5 2. Nf3 d6 3. Bb5+ so far.)