I have hunted three times and this year will be my fourth time in the last 12 years. I have done well. Doesn't seem to be as many deer as in the past but I think it is still a pretty good hunt. It is always fun just to hunt something new. If you were successful where you hunted last time I wouldn't worry about knowing more than 15% of a unit. I would have to say that I have only hunted one area every year and don't plan on doing anything different. I think some people get in a hurry to change ground to quick. If there are deer there, they will show themselves eventually. That is what we count on.