Not only does RUN have a higher PDT mitigation cap (75% with Epeolatry, compared to 68% with Burtgang) and higher party magic mitigation, it ALSO does more damage (with a 2-hand weapon!). It just makes no sense why RUN is a better tank (especially for end-game content) and also a moderate damage dealer. If nothing else, put 'Physical Damage Taken II -25%' on Burtgang.