If it wasn't Sheila's blood whose was it? On the assumption it was Sheila's blood what viable options for a source exist other than 'drawback' as the jury was told at trial?
If I knew that the blood was 100% certain it was Sheila's blood and no one else's I would have to switch to guilty, but that's not the case. All we can say is that the blood matched 8% of the population, including some of the relatives blood groups.
Sorry I do not accept the silencer evidence at all, there were two silencers for a start. SJ thought so much of it that he just chucked the silencer in the boot. DB's witness statement where he first says he saw the blood etc. while at WHF then latter in another he says he saw the blood etc. over AE's house is just unacceptable.