Coexistence of user and SuperDuper! entries in crontab

[stumpjumper]

I went to add some entries to my crontab and saw entries that indicate to me that this is where SuperDuper! is scheduling its backups from, which is fine. However, I was wondering, if I add my own entries, will SuperDuper! whack them the next time a SuperDuper! schedule is changed?

If possible, could you explain in general how SuperDuper! goes about editing the crontab and if the user's entries and SuperDuper!'s entries can coexist?

Thanks.