Could a coaching system be implemented?

A simple-ish system that allows players try and teach lower skilled players, checking mmr. players that want coaching would sign in for it, and players that want to coach would sign on to coach. coaches and coached players would not be allowed to be on friends list beforehand, and the coach would not be able to play games with the coached player. instead they would get a live feed to the coached players game from the coached players perspective, and would have the ability to type in whispers to the player they are helping. after the game they would be able to bump up or down the players grade by a letter. so they could put it from A to B or from A to S.

What would this system achieve? It could help new players learn the mechanics in the game, that you keep trying to push for older fans. it could help lower tiered players learn how to play at a higher level. It could technically lower toxicity, as coached players should be able to lose coach players, and likewise. coaches should gain ip rewards, as well as chests if the coached player earned it naturally. perhaps let the coaching system be a way to gain keys easier, but another part would be to help supports and tanks to be more capable of earning the higher rewards.