There's a fine line to walk between simplifying information and dumbing it down so that it's useless. Concepts need to be understood. That's the challenge for anyone in training, but especially so for on-demand training, where there is no direct contact between a learner and the trainer. In face-to-face situations, there's a chance to discuss and clarify, to draw on whiteboards and to use your hands to show movement, direction or structure. Personally, I have the dubious honour of being one of those people who, when I'm on the phone, acts out the thoughts, or draws out the concepts...it's a challenge...
Online, we have one shot to get the concept across, and we have to make it work or we lose the interest of our learners at a very rapid pace, and then there's no benefit from the training. That's why we rely heavily on animations to take out all the visual 'noise' of a video or photograph. Here's an example from a section of a course that deal with the concepts of heat flow, windows and comfort. In the course, a voice-over states the concepts for auditory learners, and a downloadable pdf document is a click away, so that learners can review the concept in writing if that is the best way for them to lock the information in.
