Last time CO2 was this high, the world was underwater? NO, actually

Last time CO2 was this high, the world was underwater? NO, actually • The Register:
"....the problem with this is that over these sorts of timescales, areas of the Earth's crust rise and fall as much as the sea does.
And nobody thus far has taken account of that - it has just been assumed that the rocky coasts have remained fixed with respect to the centre of the Earth, which means that the studies thus far have been - basically - wrong.
"No prediction of ancient ice volumes can ever again ignore the Earth's interior dynamics,” says Rowley."