As an intervention strategy, I've employed a similar tactic t assist my learners in learning better. I grouped the learners into groups of 6 to 7 and assigned a gifted earner to each group to be their mentor. The only problem is the class size. Having 50 plus learners in one classroom creates an issue. But it is still a brilliant strategy you've written about here.
RE: How To Apply "Everyone Is A Teacher Here" in Your Classroom : Tips for Teachers