The cap connects to Rounded chronology through counts
Rounded chronology acts on declared row quantities before those quantities are accumulated. Regular births use rounded begetting intervals; theoretical Regular deaths combine rounded begetting and remaining years; Cumulative chronology rounds lifespan counts. These procedures can disagree because rounding a sum need not equal the sum of its rounded parts. The complete comparison fields retain each local rounding residual and carry it into earlier boundaries by ordered addition.
The SP cap fits this account cleanly once its inclusive counts have been resolved. Nearest-five rounding preserves order, so rounding the smaller of a lifespan and its capacity gives the same result as taking the smaller of their rounded values. Across the complete nine-row SP field, the three clipped counts become 845, 720, and 655, and the same three rows remain strictly reduced.
Rounding the date labels first performs a different construction. For those same rows, separately rounded births and Flood start yield capacities of 846, 716, and 651. They do not replace the resolved count results. Relative to MT, the changed SP rows contribute rounding residual differences of zero, minus one, and plus four. Their combined plus three explains the established Cumulative comparison changing from minus 608 to minus 605. The connection rests on the source counts and their residuals, not on independently rounding final dates.
Sources: File51a §3.4, §§16.1–16.2, §17; File18 §3.1, §3.1.3; Research Strategy §5, Stage F.