No, beat them down to within no blue on the life line and it wont make any difference in the post tame values. AND I would beat them to no blue as they have plenty of life left, leave em any red and they will punish you.
BUT
It will barely make any difference in their ability to kill you either.
Some have commented and I have experienced it, If they cant run after you they just teleport on you. Same Difference your dead.
Having said that, what it does do is reduce the Fire Breath Damage and it does slow them down movement (as in walking). This can be helpful, especially if you can get a Peace on them. At 160 Barding Difficulty they are just hard to bard.