Hi Jane,
I read your qualification "it is always worth searching due to name variants, transcription errors and new information that may come to hand" and wonder what the source of *new* information could be?
It is widely known that the NLI gathered all extant (RC) registers for all Parishes of every Diocese, and these were duly scanned in the 1950s and 1960s and later presented online with free access for researchers and readers via the Internet.
As stated by the experts at National Library of Ireland, these records are "for the majority of Irish people who lived during the 18th and 19th centuries, the only record of their existence." Ref: https://www.nli.ie/en/parish-register.aspx
As such, these NLI films fall under the category of Primary Records which always rank highest for validity due to their originality.
As the registers were maintained by different priests, clerics or clerk, the scripting of a name, surname was not always consistent. Example: a cleric or clerk could record Maguire, while another could write McGuire. Hence dealing with name variants is standard procedure, especially for Irish records.
The variations of surnames from the same family group are astounding: Nulty, Anulty, McNulty, MacAnulty, McAnulty .. and so on are considered the same surname, as the written version depends on the scribe. Another that comes to mind is Laverty and Lafferty.
Being mindful of spelling variation is vital when reading through the NLI films or other records. Relying on transriptions, instead of reading the orginal (primary) documents and keeping eyes and ears open, is counterproductive. The chance of missing a relevant record or clue, is increased by reliance on secondary and derived datasets. Always use primary (original) data FIRST. No. 1 rule of Research, in any field: genealogy, forensic and so on.
As for 'new information that may come to hand', this is improbable. Old newspapers have been scanned, parish the ceremonies/rituals of Baptism, Burial are usually recorded once per person, while Marriage is nil, once, twice ....
Useful primary 'new information', could be a Family Bible, a Marriage Contract, a Will or unofficial communication or written note/postcard/burial prayer sheet, retained in a descendant's papers. Such privately held records rarely appear in Public sources, hence the importance of DNA, so that people can combine their research efforts and share private records.
The second research principle is locating independent supporting evidence for 'information that was not available anywhere else'.
Commonsense validation procedure for "information not available anywhere else" entails solid verification.
(1) What is the source? Public or private.
(2) What supporting documentation is available?
(3) Is this 'support' independently sourced, or merely a re-write of the *new* find?
Unfortunately 'Family History Research', has become a commercial industry, with many enthusiasts buzzing around like bees at a honey pot, waiting for something 'new' to turn up! As a result, the principles of research methodology are swept aside, ignored or dismissed in the hope of finding the 'right record', from *new* releases by Company $XYZ.
Research methods are important in Science, Criminal Law and Genealogy (aka Family History). The practice of research methods is really commonsense: Fnd a record, validate, verify by crossreference to primary records before locking in.
