according to the geddes/meade book, to remove the handle you have to remove a long bolt that is inside the cabinet ... more-or-less in the center of the rectangular handle box. The shaft the handle turns is hollow and the bolt goes thru and jambs the handle in place.
I don't think you can alter the position of the handle. It goes into a hole in the shaft then gets held in by the bolt. I guess once you get the handle out tho, you can bend it and know you can replace it. You can probably turn the handle around and have the bolt hold it in place too ... don't tighten too hard since you can shear the bolt.
I vaguely recall seeing people use a rope-handle-cup arrangement so they could sit lower. The cup fit snugly on the knob and the rope with t-handle let them pull the handle.
I'd guess the knob is molded on or otherwise permanently attached so people don't wander off with them.