Perhaps because it looks like an attempt to include as much negative information about one side of the conflict as possible? Much like the section of dubious merit above it which includes the hilarious allegation that RFK's assassination was fallout from the I/P conflict. If internal Palestinian violence shapes the I/P conflict in a major fashion it would be beneficial to include how. It's like including a section on the USS Liberty, Rachel Corrie or King David hotel bombing here; there's no point beyond innuendo.