For my seafishing with 10 - 40lb lines I'd always use a grinner (uni) knot but when I've tied this in 4lb fluoro it makes a real pigs tail of the tippet. I've been sitting here this morning (peeing down so not going fishing

) practising the Davy knot and I've also found that it sometimes unravels under pressure. After reading some of the suggestions on here I'm now tying it with 2 extra tucks and it works fine, certainly strong enough to pull a kitchen chair across the floor (Ah, the things we do when denied our sport

). So if ever there's a rise of wooden furniture at my local res I'll be ready