A very quick look at my Bedfordshire/Northants references has turned up the following John Keeps: One born Northilll 1624 One alive in Bozeat in 1594 (known only from a will) One alive in Ecton 1596 - known only from a deed Another one born in Ecton 1584 One born in Sywell 1592 Another one born in Sywell 1608 One born in Walgrave 1626
All but one of these John Keeps 'disappears' (i.e. there is no record of any marriages or burials.) There are probably many more examples - especially in Berkshire, where the surname was commonest.What is apparent is how sketchy parish records are. If you check on property deeds, wills, etc you turn up many more individuals besides those who are known from the parish records. I think we are looking for a needle in a haystack here.While it would be interesting confirmatory evidence to find that a known emigrant had 'disappeared' from the English records, you simply cannot use such negative evidence to identify the emigrant in the first place.By itself, the fact that an individual 'disappeared' means nothing: many people were baptised, married and buried without any kind of record. Our only hope is to turn up some positive kind of evidence.