The spell evolution surge allows a summoner to grant his eidolon temporary evolution points that can then be spent so that the eidolon gains the evolution large.
An unchained summoner's eidolon can benefit from spells cast by its summoner that normally wouldn't be able to affect it, like the spell enlarge person.
Because the evolution large could've been gained naturally, can a temporarily large eidolon then benefit from the spell enlarge person?