I think you got the concept confused, checkpoint doesnt force a log switch but I think you've got that concept the other way round so those 2 parameters you are mentioning will not force any log switch even they are set very low.
Now you ask why there are logs even there arent any activity, I dont know why this happens but the database I have administer so far I havent faced any kind of these problems although these problem some people have mentioned already in this forum and the suggestions were either this is kind of bug or there were really things going.

Anyway those 2 parameters doesnt force log switch!