The "morons" as you refer to them would be the medical community according to you. Its a common practice ( one which i personally follow) to let the pin stay in for a few seconds to let the oil disipate a bit before pulling out. I have had numerous instances where when pulling out immediatelly after the shot a small amount of juice came back with blood. This is caused when you go thru a vein close to the injection spot. The blood from the vein tends to lift the oil you injected to the top. Now if you had a completely clean poke which sometimes happens and were lucky enough not to hit 1 vein on the way into the muscle then that is well. But it is common to go thru a vein when going int othe muscle. It does not matter if youa re using a 1.5 " pipe you may still loose a small amount of juice when blood comes to the top carying with it a small fraction of the liquid you injected.
That is why it is recomended to wait before pulling out. Now many doctors do not do this. They simply do not care if you loose a few fractios of a CC. Most of the people on this board however do. The same goes for aspirating. Many nurses and doctors do not know or dont want to correctly do shots. There have been many instances when going in to the doctor he did not proceed to aspirate. I now have a good doc who is very knowledgable. Before hand when i was seing doc's i oftenhad to remind them of what is the correct way to administer a shot, and treatment for that matter. The moral here is to get a good doctor, because a large percentage know less about medicine than some people on this board. Then again a large percentage are true heroes.