I agree with what you are saying but what you are doing is blindly following the law well in this case the law is wrong because i have used most forms of trail docking procedures and I can assure you this is the most humane ,that is why I am using it.I will leave you lot alone as long as you are not compromising animal welfare. I don't believe that docking is always necessary. I do believe you are likely breaking the law using a hot iron without anaesthetic. Ideally you would also give painkillers too. I bet none of you are. There is some work to show that a little bleb of local anaesthetic at rubber ring application removes almost all of the negative behavioural responses that are observed - I don't know anyone doing it.
Many farmers just want to stick their nose to the ground and do what they have always done without thinking about why they do it and whether it is necessary. Getting on a high horse because our welfare standards are better than NZ because we can only use rings for 7 days and they can for 28 just goes on to prove my point.
If you can't farm sheep humanely and economically then don't farm sheep. There is going to be increased external pressure on these things - I have no doubt. I am also certain that many farmers have never left Ia significant number of sheep undocked or uncastrated to see what happens. Remember when these practices came in the fly products we have now simply didn't exist. Personally I have seen far more sheep stuck that have been docked - it's not a magic bullet.