No it wasn't this is a myth that has been busted over and over again. Ghorn was no more effective during a void or arc burn than a rare lmg or rocket launcher with h&h or tracking.

Correction on void burn a horn did more damage than the truth

Nope. I can't find the post anymore but there was a comprehensive damage test of all legendary and exotic launchers. Basically gally did about 5k damage vs a major or ultra of the same level. Every other launcher did about 3.5k damage. Now void and arc burns added a 3x damage modifier 3.5×3=10.5k damage per rocket. And then if you take the example of omnigul w/ her arc shield and you using an arc launcher. Against shielded enemies using the correct element is about twice as effective as not using the right element so recapping. 3.5×3×2=21k damage (then the standard 10.5 each rocket after the shield went down) Vs 5k. That's it (Note. I can't find the exact post so I'm just going off memory here but even if legendary rocket launchers only hit for 2k they would still do over 6k with the burn and still be more effective with a burn) Now there is one argument that does support your thesis of using gally no matter what. [b]Boss Flinch[/b] with gally your dps is spread out over a longer period of time while the wolf pack rounds hit the target keeping them flinched. This can obviously be a valuable asset when dealing with burns as obviously those burns effect you just as well as the boss. [b]TLW[/b] [b]Gally[/b]is the best when there are NO burns or a solar burn. But in other burn senario you should switch to a weapon that will utilize that burn to its fullest.

From personal experience against sekrion with void burn the ghorn out dpsed truth