If it was a nutrition/stomach issue, then coming back for Chicago makes sense. He'll still have his fitness and Berlin was really just a 15 mile marathon pace effort followed by a cooldown jog, so it shouldn't have depleted him too much. I think he at least needs to run 2:11:30 anyway. I don't think he has that time in the bank as Boston isn't eligible as a time qualifier. He'd be taking a risk that he can get it at the trials if he doesn't run something else this fall