I don't know why I even bother with this site if all you get when you try and answer a question is somebody just patronising you. On the 767 we do have an issue with the brakes and therefore when we brief the departure we would only make an immediate landing for an uncontrolable fire. For pretty much everything else we would dump fuel. If enroute, you can have the centre tanks empty in less than 20 minutes for most of our routes, so in most cases there would be very little advantage in not dumping fuel.
In the case of some aircraft not being able to dump fuel, these generally don't have an issue with stopping distances and don't have a major difference between max. take off mass and max. landing mass, ie. the 757 only has a 20 tonne difference where as the 767 has a 40 tonne difference, hence why some aircraft need to dump and some don't.