Facebook activity question

[tinpanalley]

This seems to crop up a lot and people ask me because I'm their "internet/computer guy" but I have no idea how this works. The question is, is there any point to going through and deleting Facebook activity or using an script to automate this if you're going to fully delete your account anyway? Some people say yes, because it's a way to ensure nothing remains, others say no, you're going to effectively wipe your activity log anyway by doing a full delete anyway.
Anyone know something more concrete I can tell people who ask me?