Martin,
Brand new to this site from the US. I do all of my own butchering and grinding of whitetails and I have to tell you I learned a thing or two from this post. Fantastic work. Breaking the joints rather than using a bone saw is the way to go, amazing how many people here I cannnot convince of that. Also I use every conceivable scrap for ground meat, necks, everything. Lots of those are wasted here in the US, I just can't bring myself to waste it.
You don't mention heart, liver, etc. What do you guys do with it in the UK. I used to eat organ meat but due to the high cholesterol co