Chris, the key is to tie your work to aspects of leading, directing, and guiding Project Management within all the knowledge areas. For example on one project, you conducted research. That is executing, but were you in charge of the deliverable, did you communicate your findings and inform stakeholders. If so, you probably were involved with initiating (stakeholder analysis), planning (plan communications management), so on and so forth. If you honestly cannot relate your experiences under the knowledge areas and place them into separate and distinct projects, then I agree, PMI might not qualify you.