Here's something I didn't know:
As Nuthall (2007) has shown, 80% of feedback a student receives about his or her work in elementary (primary) school is from other students. But 80% of this student-provided feedback is incorrect!80%.
It's always worse than you think.
So I guess we can safely assume the peer editing thing won't be working out.
The Hidden Lives of Learners by Graham Nuthall
review of Hidden Lives