The new Signet of Inspiration

Trying to make new comps I stumbled upon a weird behaviour on the new SoI active part.

It seems like SoI extends the duration of ALL stacks for intensity stacking boons like might. And for duration stacking effects like quickness or alacrity, it basically adds 5x 1 stack of each boon.

This means, if you put enough mesmers with SoI in a squad, you can extend the same 25 mights indefinitely? And it also means that you loose quickness when SoI on quickness, thanks to 5 stacksize cap. WoA, TW, SoI together would be, in the moment you cast SoI be 7 stacks, but only 5 biggest remain -> SoI becomes 3 seconds instead of 5 seconds.

So, is this a bug? Or intended? Im not sure. But it makes SoI VERY powerful for intensity stacking boons.

Isn't that the intended behaviour? If it extends the duration of all boons, why would it extend the duration of only a single stack of might/stability?

I think they switched it up. Because 5x 1sec makes more sense for intensity stacking boons, 5x5 sec for duration stacking, since they become "one" stack. As it is, intensity stacking is OP, and duration stacking you never get more than 4 sec out of it on boons like quickness.