I'm not sure that it's worth getting too fanatical about this. We're trying to understand what's happening in our real-world shaving after all, and if we try to go for some sort of theoretically pure results we may miss what's really happening in our bathrooms.
For example it may be that "strop contamination" is actually critical for proper strop function. Maybe the little bits of oxide that are coming off the razor as it rusts are acting as an abrasive that keeps the razor sharp. The guys that are reporting year-long edge lives are typically using vintage strops after all.