The flake that 'David Boutflour' scraped from the DRB/1 silencer, using a razor blade, was scraped from 'the outside' of the silencer, 'not' found inside 'it'. He told COLP investigators that Essex cops 'knew' what he had done. But he didn't name the Essex cops who knew, or what was done with the flake. Boutflour did not have time to scrape the said flake from the other silencer taken to his sisters house on the 10th August 1985, because he said he only looked at the silencer at the kitchen table in the presence of his sister, Ann Eaton, and her husband, Peter Eaton, before they put it away in a wardrobe upstairs for safe keeping. What this means is that David Boutflour could not have scraped the flake from 'this/ that' silencer, without Ann Eaton and Peter Eaton knowing about 'it'. What's more on the evening of the 12th August August 1985 when Peter Eaton saw DS Jones and gave him the silencer, he would have told 'him' about the small flake of blood that his brother in law had scraped from 'it', and if he had got 'it' he would have handed 'it' to Jones on that occasion, and in all probability the flake would have been analysed a month before it eventually was...
No, David Boutflour scraped the flake from the 'other' silencer, the one he and his sister introduced on the 11th September 1985, the silencer (DRB/1) which his sister handed over along with the the other 'DRB' exhibits to DC Oakey on the 11th September 1985, that David Boutflour contacted cops about on the 12th September 1985. It is my belief, that in addition to Ann Eaton handing over that silencer to DC Oakey on that occasion was that she 'also' handed over 'the flake' her brother had claimed to have scraped from it. Cops must have transported the flake to the lab' in time for the blood expert to start analysing the flake between the 12th and 19th September 1985...
Cops, relatives and at least two lab' experts, Fletcher and Hayward must have been in on 'the frame up', because the flake of blood attributed as being exclusive and unique to Sheila Caffell, was 'not' found inside the silencer. There is every reason to suppose that It was not originally scraped from the outside of the silencer (either), we only have the word of David Boutflour, he could have made the story up, he had access to the bloody crime scene, and the bloodied knickers belonging to Sheila Caffell...