They have a public Courses page which showcases some of the major courses from their library right out in the open. It looks like each course shown has it’s own landing page and is available for sale separately. This is a similar strategy that I use here at Blog Marketing Academy where certain courses are available separately. Each one functions as a front-end offer, essentially, with the upgrade to full membership as an upsell. They’re then positioning the membership as the obvious money-saving option.
In professional diving, checklists are used in the preparation of equipment for a dive, and to ensure that the diver and life support systems are fully prepared before they enter the water. To a lesser extent, checklists are used by a minority of recreational divers, and by a larger proportion of technical divers during pre-dive checks. Studies have shown checklists to be effective at reducing the number of errors and consequent incidents.