Hello Mia,
well, you wrote, that you just want to implement the setting of the default parameters for the create-pass. Users imported through the initial load already have an account and therefor the modify-pass would trigger for them and there you should keep the parameter-line commented out.
I'd say then the existing parameters wouldn't be overwritten, because for new accounts there is none and for existing accounts the create-pass won't be used.
Tero, what do you think?