Auras in Alpha's Howl question

Hi there,

I have Alpha's Howl that gives me 8 mana reserved, and i have a vitallity aura that is 40% mana reserved, by my calculations,if i put the gem in Alpha's Howl, vitallity will becaume with 32% mana reserved,but that doesnt happen.The mana reserved becaumes 37 and i dont know why?

my skill tree if helps: http://www.pathofexile.com/passive-skill-tree/AAAAAgEAAdwEBwSzBS0GDgn2C2EMXw3NEFgRDxEtFCAUsBo4HKcczh8CJy8n1SftKPorUCycMjQ1kjwtPQ89_EGHRZ1G10wtTP9TUlOlWGNboF8qXz9hIWP9aHRo8nGFdFV07XgNeWh65nrvfA58g4IegpuCx4TZhO-HZYzPkFWUoJo7muCiAKdVqW6smK9sr7e18rc-uJO-isAawGbBBMRYxLjE9sauxtjN-tR81abV-Ni92mLbC-Fz4urr5Ovu7DjtPO8O8B_2SPno_gr-VA==

It is 8% of 40%, not 8% of the 100%.
So not 40-8, but 40-40*0,08 or 40*0,92.

Ditto.

Sidenote: imagine for a moment that mana reserved would be calculated the way Drking100 meant. Then imagine taking Blood Magic keystone, plus that -50% mana reserved notable beyond it. Then imagine using, say, Heralds (all three of them). Each reserves 25% mana. But 25% - 50% = -25%. End result: the character gets "3 x -25% mana reserved", i.e. max mana is _increased_ by 75%, but since it's blood magic, it's his effective max _life_ which gets +75% boost.

Throw in more "-% mana reserved" from passives, from gem, use that 40% mana reserved aura too, and you'd end up with some QUADRIPLED max life for such blood magic "build". Oh, and totally free in terms of mana/life cost Heralds and aura, too.

Woot woot? Give!!! :D :D