Usain Bolt breaks three world records (100, 200, 4x100) at the 2008 olympics and then proceeds to break two more (100, 200) at the 2009 world championships. If he is not the best sprinter ever who is? Will there ever be anyone who breaks his records besides him? I suggest that there probably will be. Training and nutrition will improve. Some hungry kid will look at his marks and eventually take them both, or just one of them, down.
My current finite element simulation involves incorporating a stress field into a complex 3D structure then heat treating the part. The hope is that the stress fields will relax and distort the part in a way similar to what we see when we measure the part in real life. The difficulty is that we don't know if anyone has tried this before. Sure it should be possible but it is very complex to assign unique tensors to 52,000 elements. There is no instruction manual to tell me how to do this or even if it is possible.
Sure everyone has limits but who is to say that you can't run .01 seconds faster or get one more question right on the test or simplify the finite element model enough to apply a complex stress field?