Hi Jerry,
I too am new to Arginetine Tango, but here is my take on whether the cross is led. I have had teachers teach it both ways, but I personally believe it should be led. Because there is so very much for the leader to learn at the start, it is convenient for the instructors to have the ladies just cross automatically if the man walks outside partner for three steps. But once you get better at leading, in my opinion EVERYTHING should be led. A good follower will respond only to your leads and not to any mimorized pattern or step. You lead the cross by rotating your upper body and knowing exactly where your followers free leg is and where you want to place it. This takes much time and practice and I am not there yet, but on good days with good followers, I have had the wonderful experience of being one with my partner and the music. When it happens, you will both know, and it is wonderful. Best of Luck