I think in the video of Casey B. on the July 31 WOD shows him squatting heavy - no spotting stands.
I use squat stands but no spotting stands. I've only had to dump the weight once (obviously I am not trying hard enough) at the bottom of my squat. I wasn't aggressive enough in dumping the weight and the bar rolled right down my spine. It didn't cause an injury but it was not a pleasant feeling. I wanted to get spotting stands after that but decided not to. I think it's too much of mental crutch knowing you can just bail on the lift any time.