Convergent Spells

Convergent Arcane Spells are when two different schools of magic can replicate the same effect. Two completely different methods to arrive at the same end result. The most well known Convergent Spellsa re "Fly" and "Overland Flight".
  Transmutation has access to "Fly" and "Overland Flight" and Enchantment has access to "Fly" and Overland Flight." Both let people fly. But Trasmutation version lets the target grow temporary wings and the Enchantment version lets the target repel gravity.
  There is normally no benefit to learning both versions of the spell, though they often have overlapping optional prereqs.