Hi Paul,
With the info you have supplied me, we have solved the puzzle of this job.
The position was very important and was created when The Parish replaced the Manor or Monastery as the area of local government in 1600.
The system of parish government was abolished when Parliament created county,town and district councils at the end of the 19th. century.
In 1900, the classification of the job was as follows:
The Parish clerk should be 20 years old. Known to the parson as a man of honest conversation and sufficient for his reading, writing and competent skill in singing. {Canon 91 (1603)}
Functions: Reading the lessons and epistles, singing in the choir, giving out the hymns,leading the responses,serving at the altar and other like duties, opening of the church, ringing the bell, digging graves if there be no sexton.
The Parish clerk would enter records of births,marriages and deaths into a rough book, which the vicar would copy into the Parish Register. (Hence the problem of errors and interpretation). The Parish clerk was the vicar's secretary, accounts clerk and even bouncer. (I would also say "general dogsbody"). He collected fees and wrote a list of banns for future marriages.
Being more of a social equal to the parishioners, he could be approached to act as an intermediary to inform the vicar to visit the sick and dying.
As my great grandfather held this position in 1860, I think it reasonable to argue not only were these his duties but possibly a few others, as a spill over from the old Parish government system.
Once again thanks for your help and the church of St. Leonard, Wixoe, Suffolk is on my list to visit, when next I am in the U.K.
John