With MSR Pocket Rocket, 1.3L Evernew Ti Pot, no windscreen, + 60 F, mostly calm, outdoors, I observed:
2 cups water, Full Throttle = 6.9g (0.24oz) Fuel, 2:10
2 cups water, 2/3 Throttle = 5.7g (0.20oz) Fuel, 2:40
4 cups water, Full Throttle = 12.9g (0.45oz) Fuel, 5:00
Based on my results, I would expect about 0.34oz of fuel used at full throttle for 3 cups. Your conditions would be more fuel intensive with the higher winds, but you're recording about 80% higher than I'm extrapolating which is a lot higher.
I wonder if the small pot diameter is hurting you. A windscreen like the MYOG one currently posted on the front page of BPL would be worth researching.