As obscure as this might seem, you have to remember that absent a male in the line these guys would have to back up to find a line that had a continual male line down to the present day.
Odds are the current claimant under those conditions is a fellow who was born and raised in Minneapolis, MN.
The French had the same rule when they were ruled by kings--the descent had to be entirely in the male line. When Charles X was forced to abdicate in 1830, and they didn't want to hand the throne to his young grandson, they went to the nearest cousin who went back entirely in the male line, and he became King Louis Philippe. (He was descended from the brother of Louis XIV.)
Shakespeare has a passage in Henry the Fifth, Act I, Scene II, where this rule is discussed:
"In terram Salicam mulieres ne succedant,"
"No woman shall succeed in Salique land"