As seen above the tilt is to allow the gear to go in the well, but if you look at the leg itself it is tilted back so that on landing the inner leg is driven in a straight line upwards. So if you pivot the leg at its attachment point it will go into the well at an angle as thay say picture says more..
Boeing 767 Main Gear Question — Tech Ops Forum | Airliners.net half way down the page explains it all