I wasn't referring to the difference in values, but the difference in meaning - though I could be misunderstanding, you appear to be defining "hydration" both a

I wasn't referring to the difference in values, but the difference in meaning - though I could be misunderstanding, you appear to be defining "hydration" both as an exclusive percentage (75 water + 100 flour = 75%) and an inclusive percentage (100 water + 100 flour = 50%). Edit: Nevermind, just saw your correction!