Extracted from the latest DNA report from Chris Pomery at Pomerology
The first major "family" is the 600+ member tree I call the "Wiltshire tree" (FR 151 in the database). Basically, all the records for Pumroy/Pomroy in Wiltshire appear to resolve down to a single tree headed by a Thomas Pomroy b c.1670.
The second "family" are those that descend from C17th Cork in Ireland. Although these families have not been conclusively documented to be the one and the same, the testees' ancestors all hail from the same place and have long assumed they are related, a hope that the DNA tests have largely confirmed. Two who took the Oxford test are identical to Chuck Pomeroy whose 25-marker result is almost identical to one of the FR 151 25-marker results.
One is a testee in England whose GF was born in Toronto; we know nothing more about his family.
A second is Richard Anthony Pomeroy in Australia whose ancestor married in London in 1807 and appears, as we presently think, to trace back a century earlier to a village in east Cornwall (which is some distance from Dorset/Wiltshire!).
Members of FR 151 are Barry Robert Pomeroy & Ed Pomeroy; of the Irish group Chuck Pomeroy, Barry P Pomeroy and Richard T Pomeroy; and of the Cornish group Richard Anthony Pomeroy.
One final point. The "Eltweed DNA signature" cannot possibly be linked to that of the only tested descendant of the Viscounts Harberton, understood as the direct male line from the ancient family.