Is there a mathematical explanation to that?
Cause when I try to evaluate crit vs. +heal it tends more to +5 heal = 1% crit.
Of course some of my assumptions could be wrong:
For our 3400 AE ward I calculate:
+25 heal = 3425
+1% crit = 3400*(1+0,15*0,01) or (99*3400 + 1*3400*1,15)/100 = 3405,1
Based on this I calculate the resulting heals for all our heals.
I also consider having a basecrit of 45% and a basic healmod of 400.
The result however always is in favor of +heal in a 25:1 ratio.
For example:
Im Standard_Defiler_Guy.
I have an AE Ward (I use this one because this ward benefits most of %crit) that wards for 3400.
Now I have a healmod of 500 - my ward now heals for 3900.
I also have some buffs and specced AGI. So I have like 45% critheal.
In average I ward : (55*3900 + 45*3900*1,15)/100 = 4163,25
So now I have this ring from the new quest with +75 heal.
On the other hand I just might use the 4% crit ring from Tomb of Thuuga.
So I calculate:
+75 heal ring: 3900+75 = 3975 with 45% crit => (55*3975 + 45*3975*1,15)/100 = 4243,3125
+4% crit ring : (51*3900 + 49*3900*1,15)/100 = 4186,65
Well it is a difference of 56,6625 heal after all - which equals 1,6% of the original ward.
Of course the Single Ward benefits even more from +heal.
Heals are a bit different because of the crit mechanis ... however the min-max difference is too small to be important.
Now of course I realize that the item values from SOE and your "personal mark" point in a different direction, where crits are more important than my numbers show.
So I'd like to know where my mistake is so I can wear my healcrit gear knowing why I actually wear it - and not because "it has to be worth something"
