I run three (soon to be four) different sidemount classes; so the content and scope obviously differs depending on which class we're talking about. I'll assume a 'basic' sidemount class; such as the PADI Sidemount Diver, is the object of discussion here.
I've seen enormous variation in the quality and breadth of sidemount training given - primarily determined by the instructor's own experience with sidemount, or lack of. As others have noticed, there's recently been a lot of fast-tracking to sidemount instructor qualifications and that has somewhat saturated the market with sidemount instructors who lack any real expertise. A truly expert sidemount instructor; one who has 0,000's of sidemount dives experience (rather than a '3-day conversion') is able to configure, customize and optimize a rig very efficiently, dealing with a myriad of variables personal to the student and the specific rig they've elected to dive. They will be able to translate fundamental diving skills, at a superior level, from backmount to sidemount - enabling the student to gain an immediate appreciation into the benefits of the system and what it is meant to provide them with (sheer enjoyment). They will also understand the needs of the particular student, enabling them to emphasize the focus of training towards the actual needs of the student, at whatever level of diving they participate in.
My own 'basic' sidemount course currently takes, on average (no set timescale - performance based) four days. It starts with a 1/2 day (morning) theory session that outlines the history and development of sidemount, the key concepts, pros and cons, gas management, dive planning, varied approaches and philosophies, equipment configurations, fundamental diving skills, diving ancillary equipment use/stowage and and contingency protocols. I then spend a full day (afternoon and morning) on equipment set-up, adjustment and customization; for whatever rig/s the students are using. I've taught many courses for Razor, Stealth, Hollis (SMS50 and 100), UTD Z-Trim, OMS Profile adaptions, Sublevel etc (primarily warm-water/ali-cylinder approaches).
We then go to the pool for a full afternoon of confined water training; typically 4-5 hours of intense work. This begins with initial water comfort, buoyancy, trim and propulsion. During this phase, we will hop out of the pool and make tweaks should any further equipment adjustments prove necessary. I teach helicopter turn, back-kick and horizontal ascent/descent procedures (inc. bubble check/s-drill) to enable the student to better retain horizontal trim and control when maneuvering...and for accurate stops/hovers. We then cover core equipment use skills - regulator switching, cylinder handling underwater, cylinder trim adjustment (aluminum cylinders), communications (signalling), ancillary equipment access, regulator hose management and stowage. That is followed by contingency/emergency protocols; air-sharing long hose, valve shut-down single and complete valve drill and valve feathering. During the session, we cover several water entry/exit techniques and kit/de-kit (cylinders) in the water at the surface and submerged. I also run several drills aimed at promoting a high level of equipment familiarity and muscle memory, to enable deft manipulation of the kit in-water. For those that require it, I also add DSMB deployment as a skill.
Then follows 2 days of open water diving, during which students increasingly take responsibility for planning and managing the dive (all done on local wrecks); including dive planning, gas management, navigation and team skills. In addition to further skill and drill repetition, there are numerous impromptu emergency scenarios (as some might recognize from tech-level training). Dives are recorded on video for analysis, with team-focused de-briefing.
Sidemount student on initial descent, first open water sidemount dive.
