The problem with Muhammad's article reflecting Muhammad's cultural heritage is that to do so is to reflect a specific, non-neutral point of view.  Doing so would diverge from policy and precedent set on articles of other world leaders.   The articles of John Paul II, George Bush, Elizabeth I, and Hirohito do not reflect Catholic, American, English, or Japanese POVs so to treat Muhammad differently because of his religion/ethnicity/cultural heritage would seem to violate NPOV. -