The current layout makes sense:
left side, a scrolling column = a clickable list of chapters, with nested topics and subtopics.
right side = a display of the selected topic's content with text, diagrams, illustrations and some animations.
But it is unexpectedly difficult to use. Why?
The Interface Mechanics are simply wrong:
Every time you choose a new topic and subtopic, the right side of the display is updated with the newly selected content starting at the (top) of the subtopic page.
But what also happens, simultaneously, on the Chapter/topic/subtopic list on the left side? It ALWAYS resets to the top of the list?
That's simply counter-intuitive, disorientating, and a serious loss of time.
Independent Scrolling:
The way I feel it should work is the left side (Chapter/topics/subtopics) and the right side (content) should scroll and update independently.
On the left side, the currently selected chapter, topic and nested suptopic should NOT SCROLL. It should stay where it is until the user explicitly moves it up or down.
On the right side, as now logically happens, new content should display at the top of the new, subtopic content AND that information should be separately scroll-able, as you review the multiple pages of information there.
That way, you don't have to remember where in the left hand scrolling list your last selected Chapter/topic/subtopic was AND you can immediately move to the next topic/subtopic in the list and have the right side of the screen update with the new content.
Streamlining the browsing process in this way would encourage the user to quickly jump-to, and scan through, chapters, topics and subtopics to locate the exact content for which they are really searching.
Sven
