Very funny indeed, but why oh why would you ever intentionally want a dragon to go berserk 
It was not built with that in mind, it's primary function is to calm someone berzerking or subdue a wild animal type like a shifter.
I suspect given it's possibly
ancient elvish magic and the bad blood between several branches of elves and dragons, the dragon may basically be reacting to it's elven-flavoured magic trying to subdue them, triggering an instinctive fight response, just to irrational levels.
As for why would you ever
want to make a dragon go berserk, admittedly it would be a pretty rare situation, but there have been some.
One table we sat at where this first surfaced was while on run where the Johnson wanted us to undermine a local dragon who was trying to follow in Big D's footsteps and was running for a Mayor position in the mid sized Californian city and had gotten enough of a petition going to get on the ballot.
Needless to say this was unpopular with some and we had been hired to undermine their campaign, digging up dirt, sabotaging their rallies, spreading rumours.
Of course the dragon had his own people playing counter and given that we were under strict orders of no open fighting and no bloodshed it was a lot of interesting work.
It came to a head though when there was a open meeting with the dragon showing up in a human form, and the Face was going in to try one last trick to shake voter confidence in the wyrm.
The plan was basically get into a discussion with the wyrm , literally getting in his face and drive home to the public the point that push come to shove a dragon is still a beast and not a man no matter what they look like, with the intention of using the rolled up scroll to push him over the edge.
Now ideally the concept was that an adult dragon had pretty good stats and would not go full term loco, but would basically lose control for a pretty sort time. Metagame speak meaning we figured he would get quite a few hits on the resist roll so the actual berserk would be maybe 1-3 CT with one of them being him changing back to MondoWyrmMode. Even if it was just one CT with him transforming before regaining control, it would look like the dragon lost control over a simple slap to the face.
If a little longer, we figured we could hold it off long enough for security to jump in and try to help then disappear while it was distracted.
So the Face did his verbal judo and was working the crowd up and positioning himself in front of the dragon, and at the high point of his speech slapped the Dragon with the paper just like an old fashioned gauntlet, popping edge for some extra dice to help make sure the hit succeeds. The dragon is caught off guard or he just doesn't see the scroll as a weapon or something and he takes the hit full in the face.
GM cites that the dragon is popping edge for added dice as well as it is now feeling the magic at work and it is very important to him to resist losing face like this, then rolls the now considerable pile o' dice... and goes pale.
Being closest to the GM, I look over and get a sick feeling.
Critical glitch.
Note: The dragon has already used edge for the test, so can not spend further to adjust/mitigate this.
The GM and I look at each other while the Face is eagerly asking us what's happening, did it work.. what is the dragon doing. Is the news crews getting all this?
It got very messy from there.
Needless to say we didn't get to collect the rest of the fee, mostly due to the fact that both the town, the Johnson and the fixer holding the escrow all went up in flames in the ensuing fireworks.