So our boy Captain Robard is good for two additional things.
Free healing. When you select “I want to learn combos” from the training menu, you’ll be fully healed. This also cures bleeding. So you can train against Robard with a real weapon, then use the combo training to heal.
Cleansing stolen weapons- Use a stolen weapon against Robard (training with a real weapon) and it will no longer appear as stolen in your inventory. Sadly it doesn’t work for armor too. He isn’t very good with maces tho. You can always surrender when your health drops too low