"Bear seems to always follow a gully to a stream, to a river, and to civilization.
What's everyone's opinion .... is this a good plan?"
A thought on this. In the massive majority of cases, it's very difficult to walk far in most civilized countries without hitting a road. Also in most cases, if you get lost, you still have some clue, maybe even a map, to give you an idea of where a trail or road might be, if you can only follow a somewhat straight line for a while.
I would gladly follow a trail or road before I would follow streams for one simple reason: blowdowns. Streams are arbitrarily (due to gravity) in the lowest portions of an area, and typically are choked with downed trees and brush, especially in areas with significant rains and floodplain issues. Also, a stream may wind back and forth on itself for 3 miles and over cover a half-mile straight-line distance. And I suspect the likelihood of reaching civilization, or at least reorienting yourself, is likely to be quicker via roads than by following rivers.
Lastly, it's often better to sit in one spot and conserve energy and tend to immediate survival needs, assuming folks are going to miss you reasonably soon versus tromping through an unknown area. However, this doesn't make for good television.
But if I were blindfolded and dropped in unknown territory with no clue where I was, I suppose following a river until I hit a road would make reasonable sense.