Understand that the sensor wasn't blocked because I didn't move more than 4 inches within the garage door. Fortunately the door didn't come down on the top of the car but as I backed up it hit the side of the door. I ended up driving in to the door. I realize that yes if I was watching out the back window I would have seen the door but I checked then backed up. Its fairly common for people to drive this way. I don't blame the sensors on the door or their location. I wasn't through the opening of the garage.
The homelink / GPS configuration only occurs after summons is activated. It has only occurred when pulling the car in and reaching its resting point. Since I backed up and it disconnected I thought the process was over. I never ever thought about the door closing because of it. I was backing out. Thats not how you expect the homelink connection to summons to occur. Back out - disconnect and close the door? I was never in forward in that summons process. In other words I didn't pull the car in, overshoot and back up which is when the summons would naturally close the garage door. In this case it was reverse the entire summons trip.
Anyway I still don't believe I am at fault. If your kids were outside and closed the garage door on you while backing out I think you would be pretty pissed at your kid. I use kid as an example because I guess thats the level of intelligence I now realize the homelink tie to summons is.