I was just about to post something on this.
The million dollar question I have is will this work if you're flying a non-PreCheck airline like WN or will you be limited to the PreCheck carriers?
Hopefully the riff raff doesn't start populating the PreCheck lanes though. Went through it yesterday at LAX and had to wait for someone to disassemble their stroller. Lots of other people kept trying to jump into the lane while the very patient (and nice) TSO kept herding them away.