We have always fed our 2 together, next to each other.
We do keep an eye on them but they are really very good.
They generally finish their own bowls at about the same time, then they swop bowls just to make sure the other had really finished......

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The only time one of us actually sits with them & watches them eat is on Sunday nights. Why Sundays you ask?
Well Sunday night is chicken frame night, which we feel is one meal that needs constant supervision for the 20 minutes or so that it takes them to eat their frames.