rwx5861:
If you are consistently managing 1-4 client reps even as you move from project to project, you can comfortably put 2 or 3 down in your application without fear of application misrepresentation. This is common in the consulting field where there is no consistent reporting line given the constantly changing case-like nature of the work. Even if you decide to ultimately put down 0, it will not drastically play into your final decision so long as your resume and job description clearly indicate this work dynamic.
Hope that helps,
Admissionado