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It doesn't. Because it can search for Empath, when you're going off it's at least as good as Empath and sometimes better. It's worse than Empath only when you don't have Food Chain, and in that...

I think you should be running 1x Fierce Empath, 1x Emrakul, 1x Maga and 1x Imperial Recruiter. Recruiter can search for Maga, but it can also search for Empath, which then can search for Emrakul.
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Most people will probably side Swords out. Griffins and Emrakuls aren't very good targets for it.

If it's fine when you get the Food Chain, then it's pretty much always fine. Just exile the cards you don't need and leave the upkeep cost unpaid.