Well, that's wrong. It's risen from about 40% to about 60%.
I wish they'd talk to current professionals in the industry before publishing this stuff.
Sorry but as a "current professional", 25% is correct as an average and MAYBE 35% with advanced tertiary recovery (CO2 or steam flooding)... I don't think I've heard of a single field with a 60% recovery factor (maybe possible in a karstic carbonate...) A good GOM field may have a water saturation of ~30% with the remaining space being filled with hydrocarbons. If you can get 50% of that, you're doing great (50% of 70%= 35%).
From your lips (or fingertips, as it were) to G-d's ear, m'friend. Spot on, and thanks for stating the figs outright!