Robert:

Thanks for your excellent suggestion. It took some re-arranging to insure that this new feature would not cause noticeable delays, but I have done it! From now on, whenever you first open a new voice card, not only does the bullhorn in the upper left corner go dark, but a diamond (◊) appears next to card's title on the main index. In this way you can tell at a glance which cards have already been examined!