The day formula stored for this lot is Ascendant plus the Lot of Fortune minus Saturn. Expanding Fortune, which by day is Ascendant plus Moon minus Sun, gives Ascendant plus Ascendant plus Moon minus Sun minus Saturn. The Ascendant appears twice.
Nemesis therefore moves at twice the rate of the Ascendant, one degree every two minutes rather than every four, and a birth time wrong by an hour carries it a full sign. It shares that property with the Lot of Courage, the other lot in this set built on Fortune with the Ascendant left outside, and it carries the same warning: a Nemesis read from an approximate birth time is not a placement, it is a guess with a degree attached.
The Saturn term is nearly inert, moving about two minutes of arc a day, so it fixes which part of the zodiac the lot inhabits over a lifetime while contributing almost nothing to its motion within a day. Practically, the whole variation of this lot between two people born in the same year comes from the doubled Ascendant and the Moon.
The doctrinal reading of Nemesis as the lot of Saturn, of hidden weakness and retribution, therefore rests on the slowest and least individual term in its own formula. That is not an argument against the lot, but it is a fact about it that any careful reading should hold alongside the delineation.
A night birth reverses both this lot and Fortune, and the doubling has to be re-derived.