The Thinking Behind The Tweet
We cannot practice when we don't know the what and how of task-details: we cannot teach when we don't know the what and how of task-details.
But, do not expect your teachers will be masters of work performance: knowing the what/how of tasks and doing work at the master level are 2 different things.
Mastery of tasks is rare; even the most skilled performers make errors; errors define near-term limits, however, near-term limits do not have to be long-term limiting.
Errors only become long-term limiting when we choose to give them that power.