If you run a lock, secondary or engram through TWICE and it does not erase, you ask for an earlier similar incident related to the somatic being handled.
If a mental image picture goes more solid on the second pass through, an earlier similar incident must be found.
Eventually you will find a basic incident that will erase. It will be the earliest on the chain.
Follow the somatic, not the narrative content.
If handling an assessed headache you ask for "an earlier headache or head pain".
Don't ask for narrative chains such as "an earlier fight with your mother".
The rule is invariable — IF IT ISN'T ERASING OR IS GOING MORE SOLID AFTER TWICE THROUGH GET AN EARLIER INCIDENT RELATING TO THE ASSESSED SOMATIC AND RUN IT.
This was a very essential part of R-3-R but was somehow omitted from some descriptions of the procedure.