Absolutely nothing wrong with fuel burn we have now. If you can't manage to fly with 50% gas anyway, what difference will it make switching which tanks get the gas? Absolutely nothing.
Honestly I used to drain "rear" tank of a 190A would make a big difference, or Top or Bottom of tanks in Spitfire, in reality you arn't gaining anything from it - people assume they do because they have some spotted luck with it.
Fast forward 6 years later - I haven't messed with draining my tanks period, only in certain aircraft like the F4u - only because the main tank seems to always get hit, so I leave a little gas in my wings so I can make it home in case I get hit.