The out-and-back is the whole story
It is an out-and-back, and that shapes everything. You start in the dark at 6:00 AM, climb toward Inspiration Point, drop to Tunnel, grind up Rattlesnake, link a stretch of Gibraltar Road, descend West Cold Spring into a canyon, climb Cold Spring, hit the steep Edison Catwalk (the locals call it "the wall"), and work your way out to Romero Canyon. Then you turn around and do all of it again in reverse.
So there is no coasting into a downhill finish. Every climb you got to descend on the way out, you have to climb on the way back, on legs that are already done. Pacing the first half with that second pass in mind is the biggest call you make out here. Honestly it is the whole game.