I did this recently with a student combined with low level nav...one reason we might be tempted to fly at 700-800' agl is bad wx...so off we went and did a little low level route...and then I said 'well this really isnt your day...its starting to get dark, the wx isnt improving and now we are starting to be concerned about fuel...time to think about a precautionary landing eh?'
So we then went through the motions...and went around off of the approach when I deemed it was enough for our purposes...(read low...). But within the confines of Rule 5.
If you actually land on an unprepared surface you leave yourself in for all sorts of hassle, apart from the fact you put down a perfectly good airplane etc etc...
Does this help?
FF