Isn't that a rather evasive reply. Whether or not something is considered "'best practice'" can hardly be compared with the idiocy behind introducing one's own blood into, not one, but two, silencers/moderators, in the hope that, in the event of one being missed, there was always one to fall back on, it will be mistaken for someone else's -presumably having ascertained that the blood types were similar/the same?- thus convicting a third person. As I've said, RB wasn't stupid -I believe he attended Cheltenham Royal Agg College?- the act you're suggesting occurred has rather more in common with a Frank Spencer sketch.
My 'best practice' phrase related solely to Caroline's seemingly laid back attitude towards a C1 being re-wrote. In other words, in terms of professional practice.. as a lay person looking in, it doesn't exactly fill you with much confidence does it?
I'm not suggesting that Robert Boutlfour placed his blood in two sound moderators. However, surely something to be considered is the following.
If the police are adamant that the prosecution exhibit (sound moderator) was a single entity in its own right.. but it can be proven that this was not the case and there were in fact two sound moderators with varying degrees of contaminates going back and forth.. then you have to ask yourself why these same police officers were also engaged in some kind of C1 rewriting exercise.
Like I say, as lay people looking in (if we're honest with ourselves) you wouldn't feel too comfortable being investigated by 1985 Essex Police. They could pull something out of the hat at any moment.