Come on, now. You are just making this way too difficult. You have to use common sense.
If you don't have a good reason to do otherwise, clip alternately. If the route wanders, do what you have to do to mitigate rope drag and/or protect your second on traverses.
Usually you can manage to clip alternately for your first few placements until the fall factor decreases. After that, the skinnyness of the rope becomes less of an issue. As I see it, edge cut resistance becomes the biggest source of risk.
In my experience, even on wandering routes, it is seldom necessary to make more than two or three consecutive clips on one rope. You still get SOME redundancy from having the other rope. It depends on where the ground and/or ledges are.