Now the discoverer of the first Tyrannosaurus rex tissues has released the results of some research. It appears that iron in blood has a key part in preservation. Unfortunately, the experiments were spurious because of human interference and implausible situations (such as the Miller-Urey experiment, where the trap was removed to keep amino acids that would be destroyed in the synthetic environment). The extrapolation from two years to multiple millions of years is also absurd. The "research" has some valid points, but overall, is worthy of the Nebraska Man and Piltdown Man fiascoes.
Find out the analysis of the test at "Dinosaur Soft Tissue Preserved By Blood?"