What would I ever do w/o the smart, kind BYC people?! Thank you, everyone, so much!! I thought as much, but needed verification. I also remember someone on BYC saying that all of their chicks (of any breed) that turned out to be male developed tail feathers more slowly than their female counterparts. This cockerel had nearly NO tail feathers for quite some time. We took him back to the hatchery a week or so ago, but they wouldn't say that he's definitively male & for us to wait for this chick to "man up." I guess he's done just that in a few short days.
Thanks again!!