Agreed. You certainly can't game your way into a medal, or even Dean's list. Your base level of competency has to be there, and 1L largely tells you where you're at.
But if you're on the edge of either accomplishment, then it can certainly pay dividends. And if you care enough about either, why wouldn't you do it? If you can take a class curved to a B+ instead of a B, or write a term paper with a professor who's never given under an A- to a paper, why would you take the class in 3L which is notoriously curved to a B-?
People with inside information, who are at the margins of some academic goal, and who care about that academic goal, do this all the time. It's certainly not rare, and is often openly discussed by many students.
I would say sign up for January now, and wait to contact schools until after the January exam scores are back if you would like them to consider the new score. If you completely bomb November you could ask them to wait for January scores, but I wouldn't bother contact them now.
Strategy isn't all it takes. And I'm not claiming that it will make a substantial or any difference to any particular student. I'm sure many students did very well without any strategy. But it certainly can make the difference where every shade of a grade is so important (if you're aiming for a gold medal, first instance).