A mold-tool assembly, including a stem-tip portion, and also including a resin-retaining device being located relative to the stem-tip portion. The time duration of the write operation for a page or a combination of pages may indicate whether any block or blocks containing the page or combination of pages is experiencing a physical failure. A pay-per-view method is employed in which accounting is performed in units of musical pieces. The upper end of the upper column section forms a sleeve into which a deep heel truss is set. The method comprises a step of masking the path error detection within a period from a time of the detection of the line error to an expected time of the detection of the path error.