Hi Annker
I think you must have missed the bit which said: ‘… big ones, which actually perform an important role in the garden, breaking down fallen vegetation, etc….’ It is apparently the smaller ones which eat the live plants. But if you have a problem with slugs eating plants, the best thing to do is try to get plants which slugs aren’t so keen on, or put some sort of slug deterrant around individual plants.
Re. the copper tape. The type I have seen had straight edges, but if it sticks out, because it is quite thin, it is a bit sharp. The idea is to stick it to something so that the edges do not stick out and it is flattened so that there are no sharp bits sticking out. But you would want to flatten it to prevent water getting behind it as well. I believe it works by giving the slugs a slight electric shock which deters them.
