LOL of course we have nice juicy bigggggg pots in ksro lol...
The lvl 80 mana shield (will b max for isro) is 50% absorbsion so think about this... NAKED lvl 80 pure int have 4732 hp while int hybrid (1:2) have 8555 hp... now say some one does 2k of dmg (average dmg)... the shield would make it half of the normal dmg thus the nuker would take 1k dmg(appro.) and the int be left with 3.7k and the hybrid would have 7.5k...
REGARDING WORST CASE SCENARIOS... If the opponent gets lucky and gets a double crit with sst and gsm then it would be about 4k each so with a bit of recovering in between the hits the pure would have 1.5k left b4 potting after the hits while the hybrid would have about 5k left with the added inbetween healing... yes pure int ... without the hp passives and other adding hp stuff ur still dead...
So adding some str and hp comes in... now the nuker has about 6-11k of hp and the hybrid has 11k-14k...lol only about 3-4k difference :p the pure nuker still has about 10k of hp ... so now pure int nearly tank as much as hybrid with 30-40 extra str...so why do you need to reduce ur power for hp when (unless u got a lot of HP/str adding stuff and HP passives) ur FINE
WOWWWWW I THINK I ZONED IN AND OUT OF MY TOPIC THERE LOL.. sry about my messiness.... But yea CONCLUDING MY MESS ... max mana shield is 50% for isro cap and unless int get sum xtra hp they will still die fast...so if ur poor and dont like alchemy and would risk suffering dmg for tanking ability get hybrid ... if u can afford alll of that hp adding stuff then go pure like me

( I have experimented with this skill for a while.. thats the bg for my info :p)
Hope this helps