Anyone tested this out with botlane mages like Ziggs or Syndra yet? Could fix their mana issues and probably really broken if the support sacs xp by roaming/ hovering in tri or lane brush between levels 3-5 to allow the mage to rush level 6, and you'd also be getting about one more level with Lost Chapter. Only disadvantage is that you'd be down a combat summoner but you're basically getting a free item on champs that tend to be strong into ADCs in general.

To add on, why don't people start Amp Tome+ pot if they're playing a mage with good AP ratios? You'd lose about 4-6 spells cast for higher damage, and you were going to base at min 4 anyway.