Goetia Set Bonus

My friend is wondering if that Conserve MP+8 belt would be lucrative to use as BLM. So the question I had was how often does the set bonus proc given you conserve MP. Here are the numbers I've been playing with.

Average %MP conserved: 28%
Average %Damage Bonus: 56% (Double the % conserved)
% Chance to ConserveMP (From Belt): 8%
% Chance to ConserveMP (From JobT): 25%
% Chance to ConserveMP (Total): 33%

Now from the blog I read the damage bonus is after mab and int calculations and the amount increase is proportional to 2x the ratio of MP conserved. Which Means you can get anywhere from a 12.5%-100% damage increase.

If my math is correct and I'm understanding the formula properly then the belt should add...

.08 * .56 * (% chance to proc the set bonus given you conserve MP)

The blog I read had said something along the lines of "Well most of the empy procs are 5% so I'm going to say it's 5% total proc rate" which'd be 20% chance given you proc conserve mp.

Now if that's true which i doubt it is because it sounded like bs when i read it. That would mean the belt adds an average .896% damage to nukes. (.08*.56*.2)

Now with that said I don't have BLM so i can't really test this myself but was wondering if any of you BLMs out there have any idea how often the set bonus procs given you conserve mp? I'd have my friend test it however he keeps trying to say the belt is equal to x amount of mab which is stupid and I fear his testing would reflect such fallacies.