100' is within tolerance for hand-flying, what's crazy is they allowed a corridor to be used that basically intersected (within 100') a 3 degree glide path to the runway while the runway was in use with aircraft on approach. That's the absolutely insane part. Given the tolerances of well...everything, how big tails are, how gear hangs down, this was a set-up from a long time for a mid-air collision. Humans aren't perfect and relying on visual separation here was just insane. I've "lost" visual many times for various reasons including never having gotten them in sight in the first place when the location on the box and instructions should have done it.