have a way to edit only a "part"

[allan-simon]

i.e with every h2 , we should be able to open an editor for only that part, that would make it easier to view/preview while editing

[allan-simon]

it's actually quite tricky, implement them as separate ordered fields in database ?
but then what if i want to add a new "part" in the middle (we may update the 'order' number of all next fields ?)
by doing so though, it will be easier to have several editing the same page, if we have one part by paragraph or one by "big title"

i think looking to mediawiki is certainly useless as they very likely do that in a hackish way like parsing the mediawiki syntax on the fly (which would not resolve the "several people editing at the same time" )