Skill is needed for this to be successful and motivate rather than demotivate setting up barriers. The manager may want to help the learner but faces a dilemma. Post-solution reviews are important to discuss what was learnt. Consultative B to A - the manager initiates the problem, raises it with the client and then, as a coach, helps the client generate their own solution. There is still a need for feedback on progress.
Supervisory control is minimal.
The manager may offer information and alternative perspectives - without pressing them. Coaches can wear two possibly incompatible hats. I have to maintain standards and get tasks done - within a policy remit. Deadlines have to be met.