RE: Is this a funnel?
It's really hard to say from the topo. It is 11 or 12 years old and alot of things could have changed since then. If it is relatively the same, then it looks to me like that is a long windy draw or creek bottom. Like you mentioned it has steep elevation change on either side of it. This alone will tend to keep the deer narrowed down. If it is a draw with a creek running through it, look for fingers that fall off into the creek bottom where the deer can move up and down without having to travel up the steeper areas. Deer are like us, they want to use the easiest route available. On your elevation map, it looks like the area between the Stony and oil wells has a more gentle elevation change than the rest of the draw does. I would check to see if there was any sign of a major trail in that area. Also look for crossing points on the creek, I've had good luck in years past hunting creek crossings. Anyway, that's my 2 cents, good luck and let us know how it goes.