I currently take mine to my vet. But I just learned of a vet who actually numbs the tail first with an injection before docking them. I am going to try him next. Whether or not it actually helps, or numbs it at all, it still makes me feel easy thinking they are not feeling it.
I think I would not do it at all if it was not the standard. I love their long tails as much as their tiny nubs.
My plan was to take on doing it myself, but after watching it done with the twist method

there's just no way. I have WAY to much emotion to handle it
Maybe in 20 years