This article is from the RSC/UKSC Cricket FAQ, by Ganesh with numerous contributions by others.
Ian T:
Scorers are part of the 'third team' - along with the
Umpires. As a team they must work together. Scorers
should always sit together and compare score sheets
periodically - once an over is good. The actual scoring
is only part of the job. They must understand ALL the
Umpires signals and know when to acknowledge those signals
- remember, the Umpire will call and signal to the PLAYERS
initially and only when the ball is dead will he turn and
signal to the scorers. And they should wait for your
acknowledgement before continuing.
If in doubt about anything, make a note and ask the Umpires
at the next interval. They *should* be coming to you and
checking the score sheets agree as the responsibility for
the correct score is THEIRS not yours. If there is an error
it must be fixed NOW. There is no point continuing a game for
another 3 or 4 sessions when the scores are wrong after the
first session.
The umpires decide how many balls have been bowled in an over -
they *should* be checking with each other EVERY over - look for
the little two finger salute they give each other when there are
two good balls to go - ALL top grade umpires around the world
*should* be doing it. If you think they have bowled only 5 then
TOUGH!!! If you think that was a seven ball over then TOUGH!!
Never shout out 'One to go' or 'That's over' ...
However, if it appears that the miscounting is happening a
lot you could mention it at the next interval - but beware!
It is often the scorers missing a dot ball or missing a wide
or no-ball signal that is the fault..
 
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