Various "on crit effects" are inconsistent

This isn't really a bug report, since I expect that GGG designed things this way on purpose, but for the sake of sharing some testing I did:

There are (to my knowledge) THREE different types of pseudo-"on crit" effects:

1) Voll's Protector and Cast on Crit: Voll's has "Gain a Power Charge for each Enemy you hit with a Critical Strike", while CoC has "Supported Attacks have a xx% chance to Cast Supported Spells when you Crit an Enemy".
Both of these effects happen whenever you crit an enemy, with no cap on the number of effects that can be produced. So, if you use Ground Slam and crit 3 enemies, then each of those enemies will proc the Voll's or CoC effect.

2) Power Charge on Crit: A support gem which grants "xx% chance to gain a power charge on critical strike".
PCoC works the same way Voll's and CoC work, proccing on every monster hit by the critical strike, EXCEPT that PCoC's effect is limited to one total charge gained per skill use. So if you Spell Echo a Spark, and it crits, and it hits 10 enemies and succeeds each roll, then you still only get one power charge. However, since each enemy hit has an independent chance to grant a charge, if you hit 10 enemies with a crit you will almost certainly gain a charge from that skill use.

3) Surgeon's mod on flasks: This mod, which seems to be the same as the effect on Master Surgeon, reads "xx% chance to gain a Flask Charge when you deal a Critical Strike".
From my testing, this is different from PCoC. Rather than rolling per enemy hit, this mod seems to roll once per action. So if you hit 20 enemies with one Shock Nova (which is what I used in my test, as well as Ball Lightning), you still ONLY have a 10% chance (in the case of Master Surgeon) to gain a flask charge.



THE GREAT EXCEPTION

One skill seems to act the same no matter which of the above effects is in play: Blade Vortex.
Hits with Blade Vortex are allowed to exceed the cap on PCoC. Hits with Blade Vortex also roll per-hit for Surgeon's, and one cast can grant multiple charges (this is true for both Power and flask charges).

To reiterate, for EVERY OTHER SKILL IN THE GAME, the above three categories exist. For BLADE VORTEX, the only category of on-crit effect that exists is #1, which is by far the strongest of the three variants. That really seems like a pain in the ass to balance around.


EDIT: 1) I did some testing with Orb of Storms, which behaves like BV when it comes to PCoC. After extensive testing (using Conductivity to repeatedly crit with Orb on many mobs) it seems that Orb only rolls the %chance to gain charges on crit ONCE per cast. I am confident about this because Orb has a 6s+ duration, and Conductivity has a very small cast time, so I was able to crit many times per Orb cast, and I only ever got 1 charge from it.
2) Due to my testing with Orb (and some limited extended testing with Blade Vortex) I am no longer certain that BV behaves differently than other skills. My character has "Increased Flask Charges Gained" that might have been throwing off my tests before. It's difficult to verify, as I have to gather enough data to be confident that a 30% event (gaining flask charges on crit) is NOT happening twice in a single cast of blade vortex. I don't have 100% crit, so I can usually only get 4 or so crits per cast of BV. However, with my limited testing setup, I was unable to get more than one flask charge per cast of BV. HOWEVER, I do still believe that BV is an exception in the way I indicated above, because sometimes I would get a flask charge on the second crit from one cast.
Interestingly, this changed if I used a legacy Surgeon's flask. Using that flask, it seemed that I could get many charges per cast, from very limited testing.