I contest the idea that soap and water harms or is in any way bad for the pan or its seasoned coating. Why I say this is my first hand experience with them and what I have seen my mother do for my whole life.
My mother has several cast iron pans, in fact she gave me the two I have years ago. She washes them with soap and water and has done it since I can remember. She has had them for over 60+years (she’s 78-years old) they are seasoned (as are mine) great. There is a good somewhat shinny black coating on them. And she like me uses pam to coat them after washing them.
After I wash them, I put them on the range and heat them to quick-dry the pan and while it’s still hot I spray pam on it and wipe it around with a paper towel. The pans look and work great, I would say there are a lot of ways to do this and as long as one works for you, go for it.
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You can run, but you'll only die tired.