I've driven on what you refer to as "auto-pilot" before. You're on a familiar stretch of road, and after several miles you sort of "snap out of it" and realize that you were going on reflexes and memory alone. In my case, though, what snapped me out of it was generally an external stimulus like a sound or an onrushing traffic signal.
My reaction, not knowing if the light had been green for a few seconds or a few minutes and realizing that I didn't know how I'd gotten up the road as far as I had, was to step on the brakes. No, my life wasn't saved - in fact it was endangered, because I did a 180 and could've smacked into a bridge pylon (but didn't).
Even allowing for parts of the OP to be accurate, that's the part that I don't believe is as precise as you make it out to be. If you'd accept that you probably couldn't judge quickly whether the light was green for five or fifty seconds, I think it'd be more believable, and since you're reciting something from a year ago I believe you've had time to reinforce things they way you'd like to remember them having happened.
A normal skeptic's (if you are as you claim) reaction is to realize that there are a number of possibilities here:
a) mere coincidence (add to the "auto-pilot" mode and this makes the most sense
b) you don't realize whatever stimulus it was, but you likely saw or heard something that told your conscious or sub-conscious mind, "Hmm, something's not right..."
c) confirmation bias
Ya know, we could've probably handled this topic a year ago when it happened. What exactly has you posting this rather minor anecdote now? Just curious. It seems so much like a weak attempt at a ghost story told around a campfire at Kamp Krusty.
The vase in the secret compartment was better, frankly, and that one only merited three spiders.
I'm giving this one a mere one-spider salute. Carry on.
