Hierarchy in learning technology is unsustainable. Learning is a fluid thing and it finds the path of least resistance. People learn whether you put the learning in buckets or not. When you try to contain learning through a hierarchical system like say a catalog taxonomy, you set yourself up for wasted effort that you can’t maintain.
The thing is that people have a hard time giving up hierarchy… especially learning folk. what are they gaining? Do they really enjoy sitting in meetings and deciding how to divide up the world into pieces that don’t fit when you try to put them together? I think that they are afraid that letting go of hierarchy is letting go of control. People are afraid that if there is no hierarchy there is no way to group things and the knowledge of how to group ideas is a specialized skill that they have.
The alternative to hierarchy is networked information. All elements are equal and the organizing structure is in the relationships. This is more scalable because you can keep building out new relationships between the things you are trying to organize. This is not the end of grouping but now your groups are not locked into an inflexible structure. You can group and regroup and never lose value.
We are currently building a Learning Portal that is based on networked data: learning content is all equal and each component can be related in any way that we need. This gives us tremendous flexibility over the typical LMS and yet we have had a hard time explaining the concept to our stakeholders. They have no frame of reference. Where is their value add if they cannot bucket learning into categories. The answer is in providing context around relationships. That is the secret sauce that learning folk have if only they would be brave enough to embrace it.