I used to max melee on my healers by dueling my own pet class. Find a safe area, duel, /stick 10, pet hold, go afk for the night. The Coldain city was my spot when I did it.
Make sure the pet is cornered and you're attacking from the back. No warrior pets either. Don't want to get killed by ripostes or enrage.
This method should be even easier now that there are healer mercs. At the time I had to write a macro where the class that was working on melee had to stop whenever pet got below 15%