I saw this and thought, "There's way too much separation going on here, it's killing the effect." I thought I might suggest specific alterations, but then I read backwards a few pages (yeah, weird, true) and saw that Kevin did one too.
This is a much more reserved effect on the same image, making me wonder what prompted the recreation in the first place. You definitely want to avoid a situation where the layers are adjusted so severely that you have to actually alter how far you cross your eyes in order to shift between layers; it hinders the appearance of depth.
Then again, this feels like it's moot for those who aren't tolerating the parallel images, but I would wager the same basic principles should be applied to all of the techniques available.