There has been some discussion about how much planning went into this. Let us take a look at the potential risks incurred by BG of being spotted during the crime and what steps may have been taken to mitigate them.
- Spotted by someone heading north to south along the bridge trail. Mitigation essentially boils down to checking over his shoulder as he gets to the dead-end of the trail just before he commits the acts. (Less likely, imo, is a spotter or trail cam along the trail, north of the bridge.)
- Spotted by someone along the south end of the bridge (property owner, or someone taking private driveway to one of the houses). Potential mitigation is pre-scouting each home some time prior making sure no one was home. Is it possible to see someone depart the private drive from the north end of the bridge? Additional mitigation (and less likely) are having a lookout along the private drive to the south (to make sure no one is coming home) or some kind of trail cam. Perhaps there is some line of sight from the bridge to part of the private drive to know if a car is in the immediate vicinity? Additionally, if BG knew the whereabouts of property owners near the south end, this could mitigate his risk.
- Ron Logan property. I'm not sure if there exists a clear line of sight from RL's house to the crime scene. However, if the perp knew he was not home, that would be one more source of risk reduced.
- The existence of security cameras at any home near the trail or along the trail. Could have walked in/around the trails before to ensure no security cameras, or at least his particular path contained none.
- Kayakers or fisherman on the river. Not a high risk in February, but one potential risk.
I think the crime scene being near, but not so visible, to the bridge or other properties indicates the perp intentionally wanted to reduce the chance of being seen, and able to complete the crime quickly.
IMO, the commonly believed path BG took is suggestive that he knew the general layout of the trails reasonably well and understood the lines of sight involved. I think he looked over his shoulder as he arrived to the south end of the bridge. I think he knew no one was home at the south end...perhaps walked by there earlier in the day. (Related to new BG sketch?) I think he accepted the slight risk that someone would arrive to one of the south end properties during the narrow time window (only a few minutes probably) between DTH and the crime scene. He may have believed there was no line of sight from RL's house to the crime scene. IMO, BG did some planning to reduce the biggest sources of risk and did some kind of walk through of the area to understand.
However, I don't think this requires any "mastermind" level thinking. It boils down to "end of bridge is isolated and dead-end" and considering "who could see me in this area?"
One last outside of the box thought...a drone could be helpful for scouting the area days before the crime and potentially as a lookout on the day of the crime. Not saying one was used (or even likely), but just one more possibility.