I could not agree less. While it is all very well and good for us to sit here and day, sure, I understand that all that weight on the roof raises my COG, and effects my handling characteristics, it doen't effect the fact that you can lay over your average SUV in a 35 MPH emergency lane changes manuever if you put 400# on the roof. Too much, you say?
Rack: 100#; spare tire 55#, 20g cas in cans: 150#, HiLift jack: 35#; chains, shovel, axe, come-along etc? ?#?.
Also, re. tires: I put 10 ply Michelins on one of my Range Rovers. Dumbest thing I ever did. Raised it by 1" -- good. Handled like a brick, and rode like a tank -- not good. When I took them off 30,000 miles later, they had tread seperations in 3 of the 4.