P.S. to my last post:
In this case, that means:
What does the word "until" mean in the context of WotC Spell Descriptions? (RAW)
Whether or not that analysis shows absolute exclusion of Break Enchantment, did the designers intend to allow Break Enchantment to work to reverse the effects of Feeblemind?
To answer that last question, you really have to ask two questions:
1. Did the designer of Feeblemind intend to exclude Break Enchament?
2. Did the designer of Break Enchantment intend the caster to be able to reverse the effects of Feeblemind? (Intent)
Now, if one looks to the review of statutes in the law, a most reasonable parallel, one discovers that neither RAW nor intent trumps the other, which one wins is entirely situation-dependent and usually both are argued in a case whose outcome depends upon how one sees the law.
In D&D, of course, none of that really matters except as in intellectual excercise to help ward off Alzeimer's Disease.
What matter is how you DM rules for your game.