found the contradiction i was looking for. it's kind of nasty.

in 1058, pope nicholas II started to more vigorously enforce rules against incest. the duke of apulia at the time, a norman landholder, was forced to divorce and remarry. this indicates that the duke of apulia (robert guiscard) must have been related to the ducal line of normandy, as the confused mythical history states.

robert guiscard took over control of sicily in an unclear way. either circumstance was remarkably fortuitous, or the history that exists is essentially a lie to justify his seizure of control, with the backing of the church. it is said he was the brother of the ruler he seized power from, putting him next in the line of succession. ok, let's accept that supposedly historical statement at face value.

it would then follow that robert guiscard was also the brother of a geoffrey, who had a son that entered the clergy and married into the norman aristocracy. oops.

first, note that the clergy were, at this point, permitted to marry. laws against priests marrying are actually fairly recent (and the reformists rejected them for that reason). so, there's nothing weird about a priest marrying. but, how do we explain a priest marrying into his own family, breaking the rules that the church were then recently so keen to enforce? how do we accept that the church forced the powerful duke to divorce and yet permitted his priestly nephew to marry his own cousin?

the solution is that geoffrey did not marry his cousin at all. to be clear, i'm not suggesting a reason to think that marriage that is recorded didn't happen. rather, the marriage was not one between cousins because geoffrey and robert guiscard were not actually brothers.

it is the sons of tancred from his first wife that comprise the likely historical fiction, as it was concocted by guiscard to justify his seizure of power after the death (and possible poisoning) of humphrey. so says my hypothesis, anyways.

but the contradiction that has been found does expose the lie and it can no longer be responsibly upheld.

i have conquered all of the mortals.

the only thing left for me to pwn is time.