My TOC doesn't have competency Managers. I agree all TOCs work different. Drivers competency (for our DMs) isn't seen as the biggest part of the job. I think our longest driving assessment is 120 minutes. Granted there are around 20-25 per team and multiple assessments per year but investigations can take a few weeks. Care and support, interviews, sickness, return to works, trainee paperwork, meetings, projects, etc etc. Form more parts to the whole.
I think we can all agree, there are many parts to the role and Manager is just a name, by any other rose, that tastes like a doughnut.