A critical incident is reported where a discretionary user needed to partition the spreadsheet grid into an
arithmetic series of blocks and apply a function to each, but was unable to devise a solution. The incident is
first scrutinized to explicate the reasons for the failure. Then, a new method for progressional computation on
tabular displays is described and reviewed for usability. The method increases the expressive power of cell
referencing but also simplifies the notation. The spreadsheet is shown to be a surprisingly poor artefact for
three classes of display-based problem.