I'm currently doing something similar, as many others now! I think we maybe are on the right way, especially in the diagnosis of EC, the real one.
About smiling, it was hard when lips were dry for those who tried the leaving alone method. Inasmuch they're moist, there isn't resistance anymore. By the way, I remember while leaving alone, I was used to avoid to stretch my lips, but one time I did it, then there wasn't problem anymore, in the future, about elasticity.
Given that it's a celullar accumulation, then the fact of keeping the mouth closed, it was evident it caused very much damage while leaving them alone, I think it kind of created an inflexible keratinized surface, so prevented lips from stretching, which is now avoided while moisturizing.
It's a point quite special. One thing is certain, moisturizing reduces tremendendously trauma, and reducing trauma would be one of the main keys, if this is almost the only one, to resolve this affection.