If you do these things and your legs are still sinking, trying lowering your leading arm more.
Bob, how far do you want to take this approach?
You pretty soon reach the point of deminishing returns I guess. The idea of bringing more mass in front of the lungs also starts to disappear when lowering the arm.
I think 30 degrees down is about the max for this trick to have nett positive result.
for more ideas about why legs could be sinky