Question about stacking PW with Red Tearstone

I was reading this Wiki entry, and was curious about the mechanics of how it works.  I tried using PW with the Sanctus at full health, and the drain was still more than the Sanctus could make up for.  What makes this setup different?

It is possible to "safely" use the Red Tearstone Ring in conjunction with Power Within by reducing the character's max HP to near 200, which can be achieved by being both cursed and wearing the Dusk Crown Ring with a low vitality stat, then equipping the Sanctus when both Power Within and the Red Tearstone are active. Sanctus's meager regeneration will then be adequate to offset the HP drain, keeping the player alive while maintaining the Red Tearstone effect.
 

Power within drains by percentages (1% per second) but Sanctus heals the same amount regardless. (2 hp every 2 seconds) So with a low enough health, 200 or below, the healing will either equal out or exceed power within's drain. Power Within drains off the health you have at the moment, but it takes into account modifiers such as being cursed and the dusk crown ring, so if your health is halved by being cursed, it does 1% of your halved health.

The Red Tearstone however things like being cursed and the dusk crown rings effect on health and will activate as long as you're within 20% of your max health.

Soul of Stray Demon wrote:Power within drains by percentages (1% per second) but Sanctus heals the same amount regardless. (2 hp every 2 seconds) So with a low enough health, 200 or below, the healing will either equal out or exceed power within's drain. Power Within drains off the health you have at the moment, but it takes into account modifiers such as being cursed and the dusk crown ring, so if your health is halved by being cursed, it does 1% of your halved health.

The Red Tearstone however things like being cursed and the dusk crown rings effect on health and will activate as long as you're within 20% of your max health.

 Great info to have.  Thanks.  Talk about a glass cannon build.  I've been doing a bows-only playthrough, and thought this might be interesting to try.

Actually, you can take any starting class's vitality and it will be effective.  Don't raise your vitality, get cursed, wear dusk ring and use the sanctus shield.  You will lose more health than you gain.  But, you will never lose all of your health.  With my sorcerer, I lose about 6 HP out of a total 22.  So, any class can have a viable RTSR/PW combination.