Well, greg, what you're calling "British Isles" many would call "Celtic." I know that many do so out of misguided ideology, but again there is a legitimate claim to be made that there is a Celtic background to all "British Isles," including England. I'm not partisan the "Celtic" point of view, not because I think there is no claim to be made, but because we're often arguing over names rather than over what they mean. In other words, is a Scot a "Celt" or not? But in this case, you seem to be disputing what is a very widely-held opinion of modern historians of the region, by claiming that the "Scotch-Irish" were NOT a hugely influential ethnic group in the Appalachian region. You won't find too many scholars of the area to join you in your claims.

First, I would dispute the claim that most of the place names in the Appalachians are "English-Derived" in the sense of mirroring place names in England. Sure, they are English-derived linguistically, but no one has disputed that the "Scotch-Irish" were English speakers. In many cases, place names are Native American in origin, or reference geographical or botanical features, or they're named after people. Those places that are named after English places are nearly always named after places in the Scottish borders (eg. Cumberland Gap). Remember that many Scottish lowlanders were allied to the Duke of Cumberland.

Also, remember that place-names often reflect the earliest settlers, but not the ones whose descendants are dominant today. Places named after English places may have been named by early explorers and the very first settlers, but that doesn't mean the ethnicity of the later settlers is English. Are people living in Massachusetts Native Americans? Are black people living in New London ethnically English? Am I English because I come from New York, or Welsh because I now live in Pennsylvania, or Greek because I live in Philadelphia, or Lenape because I live in a neighborhood called Wissahickon?

Finally, taking out the place name issue, your statement "if you found a group of peple in some corner of the world speaking English...playing English fiddle tunes like Soldiers Joy and singing old English ballads....applying the principle of Occam's Razor, I would say your initial assumption would not be that they were "Irish-Scots" from Ulster." isn't very convincing, because we KNOW that the Irish-Scots ALREADY spoke English, sang old English ballads and played Soldier's Joy when they were in Scotland.

So once again, I think it's disputable whether these people were "Celtic," but they were certainly a significnt part of the area's ethnic makeup. Many scholars consider them the definitive part.