[i]Originally posted by pete[/i]
Is it necessary to instead incorporate the entire continuum listed above and just change how work is done to prevent stagnation as time passes?
I don't think it's absolutely necessary but it may be useful. Many athletes find that the more advanced they become the more forms of stimulus they need to progress. Often beginners can make great progress regardless of what they are doing, so it may be best to not bother "wasting" advanced level training stimuli on them which would be better saved for when they are no longer beginners and they are in need of new forms of stimulus.