Editing Forum reference mechanisms (section)

==== Leach-donate ====
A post may simultaneously leach and donate to another post. It is important to note that the order in which the references are executed matters. By default, a post with both leaching and donating references executes leaching first and donating second, though this can be reversed by fiat.

If there are several leaching references, it is also important to note that the order in which the leaching references are executed matters – switching the order of execution may change the outcome. This non-commutativity arises because the order of references in time is different. For example, suppose <code>post3</code> leaches from an older <code>post1</code> first, then leaches from a newer <code>post2</code> which has already leached from <code>post1</code>, then you get a lesser result for <code>post3</code> than when the order is reversed.