Hey Ryan, sorry for the slow reply. I was away for more than a week visiting friends and family.
Re: the BBRx Program 1C and 1D - map them out and you'll see that they are essentially the same, alternating between the same "A" and "B" days, except that light squats are now alternated in for the mid-week squats in Program 1D's weekly schedule. You're still alternating Deadlifts and Power Cleans on the "A" day, with your Back Extension of choice on the "B" day. The difference is presentation, where the description of 1D actually starts with the "B" workout on the first Monday. So, in program 1D, you're alternating heavy pulls every 5 or 9 days , which is crucial at this stage as you are likely getting close (or already are) over-taxing your lower back with heavy squats being every workout to every other workout.
I do find it interesting that they don't use the same scheme in the Masters Novice Programs 2C and 2D, where I would think that we would need it more. But for typical reasons for the Masters, they don't list Power Cleans in those programs.
As far as how it's working for me, I can't say, as I have not been consistent lately due to various trips over the past couple of months. That and I am not currently pulling at PRx5 sets for the same reason. But conceptually, it's quite logical.
It's also good preparation for when you get into Intermediate programming, where you'll likely lose even more symmetry in your planning and programming.