Thanks Chris for your advice.  I never quite relax with my marans cockerel as he attacked me once earlier in spring and is liable to fly at anything I might be carrying like a watering can.  I stroke his back and pick him up at night with no problem.  He is hatched from a great strain of dark eggs, is  lovely with the hens, a light treader, and the chicks I've had from him have been lovely and very robust.  So you think if I give him treats (which he will immediately call the hens for) and don't get between him and his hens, I should be OK?