A mail item sortation system and method that includes an external controller for culling candidate letters in a mailing job to produce groupings of letters based on industry average weights and/or thicknesses in order to place all the candidate letters going to a single address adjacent to each other, an internal controller, interfaced with the external controller, that utilizes the groupings of letters to manage multiple letter sorters, wherein a specific letter sorter is selected to pair a calculated number of pockets to accommodate the groupings with an actual number of pockets in the selected letter sorter, and a transfer process for moving letters within the letter sorter pockets to a StatementPack machine.