I would think that the added moisture that's in the air from washing being dried indoors can be a good thing, too, though. Sometimes I hang a 'thing with water in it' from the radiators to avoid too dry an atmosphere, but if washing's being dried indoors, there's no need for this.
I remember my mother having a clothes horse holding wet washing, in front of the coal fire in the winter. That fire was the only heating in the house, and I think that was one of the reasons my mother used to buy dark-coloured clothes a lot....one of her favourite phrases was, "That's a good colour to buy - you won't be able to see the muck in it...."
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