Matt,
You have hit on some of the tricks I use to make my dough at 80% hydration. First and foremost you need high gluten, and I have found getting there through the use of vital wheat gluten is a good alternative so long as you start with a good base flour. I then do a double hydration, first 60% to develop the gluten, once it window panes I slowly add the rest of the water to bring it up to 80%. This part is a pain but it is doable with patience. When that is all done you end up with a thick glutenous "batter" that you are sure will never become dough no matter how many times you make it, lol. That leads to the next trick, folding, lots of folding during fermentation. I usually fold every 15 minutes for the first hour, then more like every half hour after that. It will transform into very wet dough right before your eyes. The final trick comes when forming the dough balls. Keep a pile of flour next to you. Once the ball is formed, or mostly formed, roll it in the flour. You don't want to work this in, you just want to coat the dough ball to make it like a water balloon with a dry skin and a wet interior, and trust me it feels just like a water balloon. I then proof in a wooden box with a floured canvas on the bottom and a damp towel on the top. I've tried this dough without the canvas and it always sticks no matter how much flour is on the surface. Throw this stuff into a 900-1000 degree oven and you will have the lightest, airiest cornice ever.... getting the center too cook is more of a challenge...