Heal Critical “Divine Surge” perk needs rework

This perk supposedly allows healing spells to crit with your magic crit chance and benefits from crit damage. However, my testing suggests the chance to crit is far lower than my magic crit chance and the benefit from crit damage modifiers might be getting added before and without respect to any healing modifiers.

With 19 Intelligence, a staff with 29 Intrinsic, and a healing bonus modifier of +255%, casting eternal heal channel (which has a value of 43) results in healing of 141 health per tick of the spell. Now, the crit damage modifier on my character is 164%. I would expect critical healing to become something like 231 then. However, it instead only results in 166 healing on criticals. This is a mere 18% improvement over a normal heal rather than the 64% I would expect. Furthermore, the crit chance occurs far less often than I would expect. My magical crit chance is 23%. After 20 trials of casting channel healing, I would only ever see the spell crit 1-2 times. This held true with each repitition of 20 casts. The binomial probability of 2 or fewer crits after 20 trials with a character magical crit chance rate of 23% is less than 13%, very rare. However, the binomial probability of 2 or fewer crits after 20 trials with a crit chance rate of 5% is around 92%, that is, par for the course. This suggests to me the Divine Surge perk is not benefitting from magical crit chance increases from equipment, weapons or perks and calculated only with the base chance to crit.

Taken together then, Divine Surge is resulting in an 18% improvement to healing 5% of the time for an average less than 1% improvement to my characters healing (a modifier of 1.009) and yet this perk costs 5 whole skill points.

Please rework the formulas used to calculate healing criticals or replace the perk Divine Surge.