I just had a thought, Grime says Eddie wouldn't alert to any edible pig products, such as pork, pork chop, bacon etc. He used piglets not fit for human consumption, by that I think he means they were decomposing piglets. Yet he took a piece of pork drenched it in petrol, burnt it, hid it, and Eddie alerted to it. Surely if you took say a pork chop drenched it in petrol, burnt it, hid it, Eddie would alert to that too, it's all pork at the end of the day and I would think burnt pork would give off the same scent no matter what shape of food it started off in, wouldn't it?
I would expect the pork to be part of a decomposing piglet, otherwise Grime was training him to alert to normal pork. He wouldn't do that because it would mess up all his previous training. This type of training allowed Eddie to alert to such things as;
The search of a suspect's 'totally burnt out vehicle' by forensic scientists did not reveal any evidence.
A 'one minute' search by the EVRD identified a position in the rear passenger footwell where the dog alerted to the presence of human material.
A sample was taken and when analysed revealed the victim's DNA.
The enquiry then concentrated it's efforts on the suspect and the EVRD located the body of the woman in a river bank deposition site.
http://www.mccannpjfiles.co.uk/PJ/MARTIN_GRIMES_PERSONAL.htm