Heh, next time I do something really messy I'll make sure to snap some pics. I don't always manage to keep the dust under such tight control. When I do initial shaping and routing for my next bodies, it'll look like a proper tornado of dust and shavings.
I'm normally a massive template hound (like you guys couldn't tell), but necks and aesthetic carves are done to suit each individual guitar. It's not much of a method, but to me, it feels like the right thing to do. So I basically go by feel, but I do have depth targets to hit and a profile in mind. For this one, I actually shifted the facet on the treble side more towards the centerline, giving a nice asymmetrical profile. It effectively disappears if you play all properly with good thumb position and so forth, but still retains a bit of reassuring heft if you do go for a full-handed grip.