To communicate the link between a competency model and development, you need to first communicate what a competency model is and does.
A competency model defines what each person in their role needs to be able to do, specifically, in order to perform their part of corporate strategy. It also defines what it looks like to be great in that role.
It seems almost too natural and too obvious that once you know what people need to be able to do, if they can’t do what they need to be able to do (a skill gap), you need to have a way of teaching them. This is employee development… and when directly mapped to the competency model, it’s competency-based learning.
For example, if one task in a competency model is “Engage the appropriate company and customer resources (systems, people, processes) to get things done better and faster”, then you want to have an activity, for example a skill practice for workflow learning, where they learn to build a project action plan that engages the required internal and external resources.
If you can talk someone through this connection at a high level, and provide them with an example, then you should be to communicate the link (and the need) between a competency model, a skill gap, and competency-based learning.
For more on how to develop competency-based learning, watch this webinar: http://webcasts.td.org/webinar/1791