ok sure this has been done, but heres my thought what if he out lives his son Alexander III and dies in 1895 leaving the Crown to Nicholas II with no Alexander III
According to the rules the next son of Alexander II, Vladimir, would be Tsar.
According to the rules the next son of Alexander II, Vladimir, would be Tsar.
Why? According to primogeniture Nicholas would be the next in line of succession, and in 1895 he would be 17 years old, he might even assume the throne without a regent.