cpu frequency in /export compact

Why to export cpu frequency value in /export compact ?
The “export compact” function was to make easier the migration from a router to another, exporting only user-modified settings.
So, why cpu frequency? I never touch it, but each time I migrate among different routers I have to check and remove the cpu entry from export compact script.
Is there any reason to export cpu default frequency?

The import tipical error message:

[admin@MikroTik] > import file=adsl_backup.rsc 
input does not match any value of cpu-frequency