Well, what the blood expert (Hayward) and the ballistic expert (Fletcher) did not want the defence getting a whif of, was the fact that human blood was found on the end of the threaded guns barrel, and also that when the cloth pull through test was done and examined, that human blood was detected inside the barrels lining, but because there were two particular tests conducted on the cloth pull through (MDF/1) and the test proved positive on the second test but not thye first, thye blood expert chose to report his findings as inconclusive!
Now, these notes, and this diagram have a significant bearing on what the court was told during Jeremy Bambers 1986 trial - the court was told that 'NO BLOOD' had been found upon the cloth pull through of the guns barrel, but that was rather misleading, the correct interpretation was that the tests had been deemed inconclusive, because human blood was detecteed in the second test, but not both...