We've spent the last year working on high gravity brewing techniques, especially for highly hopped IPAs. The main benefit is extending the amount of packaged beer which offsets the amount of loss from trub, yeast and hops. It doesn't take much, either. Just 1 to 1.5 points of alcohol higher than spec and there's often a 15% to 25% gain in volume after adding deaerated water. We like this technique best with recipes of 4% to 7% abv. Our experiments have found near zero change to perceived hop bitterness, aroma or flavor vs batches done at normal strength.