RE: 12 foot tree stand more like 6 feet
Yeah, you definitely need to move that stand, and I'd recommend having a good deal of cover around you even when you're at a full 12'
I prefer the 20' range myself, but have hunting from some 12' ladder stands with great cover (pine tree setting) and had deer within 10yds not have a clue.
Cover has a lot to do with it....