Cast on Ignite - Maximum Energy

Posting here because I can't tell if this is a bug or if I'm just missing something. Perhaps someone can enlighten me? :)

So the skill description for Cast on Ignite says that the maximum energy is equal to 10 for each 0.1 of the cast time of the socketed spell.

I put Flammability into there, which has a cast time of 0.7s. No other supports, just the meta skill and the socketed spell. It shows that the max energy is 70, which is exactly what I expect from the maths.

But if put Comet into there instead, the maximum energy goes up to 300. But the cast time for Comet is 1.00 sec, so surely the max energy for it should be 100.

So, what am I missing, or is it a bug?

Thanks!

Tyls.

I'm not completely sure, but maybe it has something to do with the +1 second of cast time in the modifiers.