It's pretty common actually (Destiny)

by Xenos , Shores of Time, Saturday, August 15, 2015, 18:15 (3485 days ago) @ CruelLEGACEY

The difference though, as far as I see it, is that even though my customer identified the problem incorrectly, there was a problem with how the guitar felt in his left hand. If Gjallarhorn's visual effects weren't apparent enough, I can see how one or two people might say "this gun isn't powerful enough"... but I would think someone, somewhere along the way would identify the actual problem and correct things accordingly, just as I did when my customer complained about the shape of the neck he was playing.

And who knows... maybe that is exactly what happened. The visual effects of the wolfpack rounds are plenty visible now, so by the sounds of things they did get visually beefed up at some point. But I have a tough time believing that nobody at bungie was aware of how earth-shatteringly powerful it is, which is why I still think Gally's damage output is intentional.

I think the problem was two fold honestly. I think Bungie purposefully made it as powerful as it is, but it was in response to people feeling it was underpowered (possibly because of the unfinished effects). In addition I think that they didn't see its power as an issue when the game was first released, but mostly because it took a long time for a significant amount of the game's population to have Gjallahorn. Now that they saw the effects of a huge percentage of the active population using Gjallahorn ALL the time they decided to balance it.

Basically all I'm saying is I imagine the truth lies somewhere in the middle. They probably knew to a certain degree just how overpowered it was, but they didn't suspect it to become as big a problem as it is.