Physical skills can erode over time placing a Door Supervisor and others at risk. It is therefore important that Door Supervisors frequently and safely practice their skills to keep them fresh and accurate. This will at certain points include formal training and recertification events, where a Door Supervisors competency in the skills will be assessed by a certified trainer. The frequency and approach to both work based practice and formal recertification events will be in line with the role, sector and employer guidance.
Nothing is better than on the job experience and the role of the Door Supervisor has changed over the years. When I first started I worked with one of the old school doormen, who's idea of diffusing a situation was to throw a person out of the premises no questions asked. With SIA regulation and CCTV everywhere those days are gone. Physical intervention is a last resort and most situations can be resolved verbally. Training does help but doesn't equip a Door Supervisor for all the situations they will encounter. Group discussions and mentoring is a good way of passing on knowledge.