Link skills not properly counting mana for mana spent

When using link skills with the occultist's Forbidden Power node it says that "Gain a power charge on spending 200 mana". This kind of works, however it seems to be offset by mana recovery.
My character has 32 mana recovery per second and using a level 1 link skill the mana drain is 15 mana per second. Using the level 1 skill I was never able to gain a power charge even though I was technically 'spending' 200 mana in about 13 seconds.
When I added some supports to the link skill I was able to get the mana drain to 36 per second, and after about 30 seconds I did get a power charge, however something seems off here as with an effective 4 mana spent per second it should take around 50 seconds.

I was thinking that the wording of spent mana would generate charges like other skills, but this seems to be not working properly.

Also I just tested it with arcane surge linked and was unable to get the arcane surge buff to trigger from spending mana with the link skill. I was spending enough mana to get my power charges (very slowly), but didn't trigger arcane surge even at level 1.

Ahh I didn't notice that on the arcane surge. However the Occultist's forbbien power doesn't say that, and seems to not work correctly.