If you look around online you'll find a lot of people identifying the flaw in Ippudo: MSG. We went there yesterday evening and were thirsty for the rest of the night. My girlfriend woke up this morning with a (suspected) MSG headache. Sure the broth tastes good -- but that goodness seems MSG-derived.
I understand that MSG is an integral part of popular Japanese cuisine, but I'm really not a fan of it. Incidentally, the Japanese theme-park behavior of the obnoxious servers, constantly chanting in a way that helps you appreciate the relative authenticity of Yakitori Totto, is another reason Ippudo is overrated.
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