Nice video. This is one of my favorite climbs. At 8:00, what you identify as Big Slide, is actually the Third Brother. Big Slide is behind and to the left of the Third Brother from that vantage point. You can see it at 8:26. Big Slide provides amazing views of the Central Range (yes, that's Marcy to the right). That final .25 mile, though, is a killer - especially in rain! Great to see the boys out there - they will remember this their entire lives.
We did this 10 days ago. Not that sketchy. There's plenty of room and the drop off, while certainly enough to cause injuries, is not as bad as it looks.