No mercy for slugs around here. I use nasty metaldehyde pellets in places wildlife can't get to, organic pellets, beer traps, snipping with secateurs, slug nematodes, garlic spray, salt and any other inventive ideas folk come up with. I tried leaving it to nature for a couple of years and I'm not going back to having a devastated garden, or spending 3 months raising plants only to have them destroyed in a single night!
Even with the above full-blown assault, I still can't grow hostas. Good job I don't find them particularly attractive!
Copper rings, vaseline, eggshells, sharp grit (even tried crushed glass once) and a myriad of other 'slug deterrents', including expensive commercial ones have absolutely no detectable effect for me, unfortunately.
Do we 'clay gardeners' have more of a problem with slugs than other soil types? There's anecdotal evidence for this which I've read on various forums over the years, but I'd love to see an actual poll done.