I have to admit that the leg offset issue can be a slow burner on your health and I think I am starting to suffer with it. My right side tends to get pains in it the next day after a long drive and my right hip area feels it most but it travels to my shoulder and arm.Only about 25% of the challenge is the footrest. The bigger challenge is where the accelerator is. Normal cars have it in line with the knee, the Grenadier has it 3" to the right of the edge of the driver seat. So unless there is some sort of physical deformity you can't sit symmetric. One butt cheek at a time going to be under more pressure than the other. And your spine isn't going to make it to a straight line. Too close and erect, longer drives will give you other stress problems with the lower legs.
Unless of course cruise control is on and you can sort of relax off the pedals a bit. Or you drive a LHD, which seems a lot more symmetric and square with the driver seat.
I have given thought about putting a cushion between the bolsters to flatten the chair out and allow me to sit slightly more to the right to reduce the offset.