Unfortunately, no. That would be nice, but it'd really be overpowered.
The way procs work is that they have a certain chance of going off (for some procs, this is 100%). The way that chance is rolled then depends on the type of power it's slotted into.
If it's a click power, the chance will be rolled each time the power is used. So a proc with a 20% chance to deal some damage slotted into a melee attack will roll the 20% chance each time the attack is used. (Or, in your case, if you slotted the gaussian's BU proc into something like build up, it would roll the 5% chance when build up was used, so 5% of the time you'd get a double powered buildup).
If it's slotted into a toggle or auto power, the proc checks every 10 seconds. Note that it is still subject to the random roll to see if it goes off. So in your case, if you put the BU proc into invincibility, every 10 seconds it will roll the 5% chance. So, on average, about once every 200 seconds (3 and a third minutes) you'll get a short build up effect applied to your character (of course since it's random it won't be *exactly* every 200 seconds like clockwork, in fact it could go off twice in a row if you're really lucky, but it'll average to once every 200s). So it will be nowhere near a permanent buff.
Honestly, the gaussian's BU proc is more or less useless, in my opinion. It might very occasionally help out, but the proc chance is so small that I don't think it's worth the slot unless you're going for the 6th slot defense set bonus.
@MuonNeutrino
Student, Gamer, Altaholic, and future Astronomer.
This is what it means to be a tank!
The value of Gaussian's is the 6-set bonus to DEF. The build up is just an incidental.
I am really not good with Procs/globals. As I understand it, if I slot a Gausian's "Chance for Build Up" in Invulnerabilty "Invincibilty" toggle, the Proc will fire constantly as long as the toggle is active and will constantly give the +acc/+dam buff?