There's something i noticed:
On most EC sufferers' lips, the affected area has pretty much the same shape/size/look. For the majority of us, it's not our whole lips that are affected. On the outside of both the bottom and the top lip (if it is affected), there is an area with pink, healthy & elastic lip skin that never gets involved into the skin buildup process.
I reckon that, in humans, there's a difference between those two areas (the affected inner and the unaffected outer one) and it has mainly to do with nerves. i licked over my lips the other day and it seemed to me that these affected inner areas are more sensitive than the outer ones. The outer areas feel stronger, much like the skin on the rest of our bodies. Especially the triangular patch in the middle of the top lip seems to be packed with nerves underneath the skin. I asked a friend to lick over his middle top lip and he noticed the same: it feels very delicate.
My unedcuated guess is that, for whatever reason, our nervous system freaked out a bit and our sensitive inner lip areas start to grow thick buildups of dead skin (don't ask me why). These lip nerves must have many many connections to other systems in our bodies, Many people see a connection with their digestive system and I'm pretty sure that there is a connection with the psyche (for the natural scientists among you: the brain and it's conduct). Some people got this just by licking their lips too often, maybe they irritated their sensitive nerves, triggered the peeling process and perpetuated it
by paying attention to it and further irritating it by picking, peeling and exerting physical pressure on them (which is pretty much anavoidable with a condition like this, it's a bit of a vicious circle there).The human nervous system is very complex and interconnected. It also works slightly different for everybody. This would explain why the triggers for this condition are so diverse.
The bottom line of my remarks is that this is essentially a nervous disorder (I have the impression that many of us have so-called "bad nerves") that is triggered by a VARIETY of causes.
The cure for everyone is different but, in most cases, multitudinous and does involve more than a bit of eating here and a bit of ointment there. For those who beat this condition, it was mostly a combination of stress management, healthy lifestyle (including healthy diet, exercising (i believe this one to be especially important because it releases happiness hormones)), leaving the lips alone & not making up ones mind about it.
I know that this is basically old knowledge but for me, the difference-in-lip-nerve-structure-theory extends it by a certain dimension. I hope you can make use of this. Good luck to everyone!