foessc wrote:"Brewers that use bottle fillers are going to achieve a fill level of 1.5 inches from the rim of the bottle. Bottles filled 1 inch from the rim will be less carbonated. Bottles filled 2 inches from the rim will be more carbonated"
I think you've got that backwards. The beer is more carbonated than the headspace at filling. After capping, CO2 evolves out of the beer into the headspace until equillibrium is reached. So the higher the fill, the more carbonation retained in the beer.
Now, your bottling method may do different things at different heights, but that's a separate question than just "fill level".
Another way to think of it: If 2 inches from the top is better than 1 inch from the top, then 3 inches is even better, and 4 inches is even better, so clearly the most carbonated bottle comes from not putting any beer in it at all!