It's not the avocado that's dangerous, it's the knife handling.
Most kitchen knife cutting accidents are due to blunt blades. I've just used a whetstone on my carving knife ready for Christmas, it's sharp enough to shave with, but funnily enough, that analogy makes most people cringe terribly...
1. Run a sharp knife around the avocado, so that it is divided into halves, with the stone still attached to both parts.
2. Hold the fruit with one hand on each half and gently twist - one half will separate from the stone.
3. Now hold the half with the stone in the palm of your hand and with a cooking knife execute a sharp chopping action onto the stone. The knife edge will embed itself in the stone, and a twisting action will separate it from the fruit.
It's easy, fast, and provided you do it carefully it's guaranteed not to cause injury - no stabbing involved at all.
in North London than in Bootle - I wouldn't know. I know that avocados are delicious though, and I know that they are not expensive when compared to some other fruits, so yes, I eat them regularly. I like them in salads with a honey and mustard dressing - they go well with my tagliatelle and arabiatta sauce.