Don,
Correct. 440 Cubits is 756 feet... which gives an error rate of 10%. You can play around with the definition of foot to lower the error rate...
[en.wikipedia.org]

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The question is was Herodotus off by 10%, or should we consider accepting a reinterpretation of his words that reduces this error to 1%?

The language of Herodotus is pretty confusing... could this be referring to area?

[www.losttrails.com]
"whose each side in every direction is eight plethra, it being quadrangular"

[www.losttrails.com]
"The field is a hundred Egyptian cubits every way and the Egyptian cubit is in fact equal to the Samian"