Can you further explain why repeat sessions are often needed for successful resolution of even a single issue in a client?

This explanation was given earlier. It is a consequence of the barriers imposed by the client’s limits in belief, coupled with the limits within the practitioner. So the question of specificity and then freedom to act both come into play in how much healing is achieved with a single Protocol application. If belief is less than 100% present, there will be a corresponding reduction in reach. If the understanding of underlying problems is more general than specific, the reach of the energies through intention matching will be correspondingly more diffuse, less precise and focused, to bring the energy to bear with greatest power on the precise need in each and every entanglement. So these factors are the reason for varying effectiveness in a single session and desirability of reapplication to chip away incrementally as the next best recourse comes into play.