Why havent we done it?
Heres an anlogy...lets compare the head coaching role to a construction project manager.
So you have a talented foreman who wants to step up into project work. You know what his strengths are, whilst being well aware of his inexperience. You are cognisant of his leadership traits, has some knowledge of contracts, can easily converse with the stakeholders and is a thorough communicator when it comes to monthly reporting. However he has never worked with PM software, never constructed a programme of works nor a budget, doesnt understand risk management, and has only remedial understanding of whats involved with quality amd procurement management. More importantly, he has never setup and planned a project, executed one nor closed one out. You talk to him about how different and stressful the job is and he is still interested, so you green light the promotion.
He obviously requires help, so you start him as an assistant PM and pair him with a hugely experienced senior PM and you send them off to knock over a $85M job due in 16 months. Once completed, you do a review (lessons learned) and acknowledge his progression but identify areas of improvement. You decide he is worth persisting with and set him up with a big project of $250M value where he will be paired with your best senior PM. 2 years later they conclude that and hand it over. He has proven his worth, has had exposure to two very different high pressure jobs with 2 excellent mentors. Time to have a crack. You hand him a small $8M job, over seen by a senior PM but he is responsible for it. Once this is completed, you reassess and determine its time to break the shackles and send him out into the world. His 3.5 year development is complete to the stage that he can stand on his own and be trusted, and youll provide further training as required to keep him up to date.
Now compare this to Benji's journey. He has been setup to fail. He has not progressed anywhere near as fast as hoped. He is showing clear signs of fatigue. You question whether his heart is still in it and whether that enthusiasm is still present. Yes he needs help. They should never have released Sheens without providing a replacement mentor. Benji should not have had a say in this.