I didn't say that soreness is always due to positioning and I have just re-read my posts to make sure I didn't!
When there is trauma to the nipple - cracks, sores, blisters, etc - it makes sense to assume that the skin has been grazed or broken by something rubbing against it. Ruling out jogger's nipple in the immediate post-partum woman ; ) the only thing rubbing against the nipple is the baby's tongue and palate.
Now, as we're all different, it could well be that some people have more friable skin than others. Some babies may have a shorter tongue, or be tongue tied, or have a different sort/shape of palate. These variables may make pain-free breastfeeding more of a challenge to some individual mother-baby pairs.
Because we can't see what is going on in a baby's mouth, we are making assumptions that there is some friction going on inside when trauma results, but I don't see why it's controversial or confrontational or annoying to say that if we see a damaged nipple then it's very likely to be the positioning and attachment that's caused it. Unless someone else comes up with some other reason I haven't thought of.
Painful breastfeeding without visible damage to the nipple could be thrush, in the absence of some clear problem with the latch. The sort of tenderness people describe that gets better over time is, I think, the stretching of the skin and the nipple getting used to the new sensation. But tenderness does not come near to describing the agonies some women have with sore nipples, and I don't go along with Bloss's idea that we should just say some people feel pain while everything gets toughened up - and leave these poor women to the pain! The sandals that give you blisters is also a poor anaology. Blisters come about because the skin is being rubbed. A baby who is 'on' right does not rub the nipple skin. The milk does not come out as a result of friction.
Cracked nipples - like you had, Bloss - do sometimes continue to hurt after the cracks have healed. This is one of the reasons why cracks are such a must to avoid - you get 'afterpains' with them. I think it may be that just like scar tissue anywhere else, the skin becomes less elastic and feeding hurts as a result.
Sometimes, I suspect there may be some underlying infection that takes time to heal, too. Cracks allow skin infections to take hold.
Kamillosan is fine for sore nipples, and safe for the baby, but dermatological research points to moist wound healing as helpful - kamillosan is absorbed very quickly, and there could be other, better products which trap moisture in the skin more effectively. Trouble is, there is a dearth of research on all of this, and we are still learning.
Lisa mentions the let down reflex as having a role to play in painful feeding. Some women (a very, very few) do feel the let down as painful, but I can't see why it would cause sore nipples.
Painful feeding which affects the breasts with shooting pains is more likely to be thrush in the breastmilk ducts.
If someone is finding feeding painful, but the nipples are fine, then it could be mastitis or thrush.
(Both these things can be linked with positioning as well - sorry! But they need treatment other than just attention to positioning.)
I said it before, there is lots we don't know about how to ensure pain free feeding.