The set-up I've been using has me testing at very low levels so I've been using stat boost/drop + skill/power/speed swap and other stat-checking shenanigans in order to increase the range on damage rolls to where it's relevant to testing, the big calc being:
0 Atk Pixie Plate Rattata Tackle vs. -1 252 HP / 0 Def Blissey: 19-24 (32.2 - 40.6%) -- 99.3% chance to 3HKO
(19, 19, 19, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 24)
The calc was made rather arbitrarily- It's Fairy Type base 40 Power Tackle with Pixie plate coming off of a 15 atk level 7 Yungoos vs to emulate 1.2x Galvanize. This calc is done vs 6 def -1 blissey at level 5.
While it might not look good because it's a "low level calc," but after doing this kind of thing enough you get used to the quirks of it. This is a totally unique damage range that is impossible with anything except if -ate and -ize abilities are 1.2x, and I hit the 19 and 24. Every single other element is controlled. I challenge you to find any combination of multipliers that make a 15 atk level 7 pokemon deal this damage range to a 6 def Pokemon with a different multiplier to a 60 base power move to disprove this, but I couldn't find one myself. Unless there's A. a change to the damage formula or B. I messed up my subtraction on the rolls in-game, the -ate boosts have been reduced to 1.2x. In all of my other testing except Galvanize, my calcs only confirmed that the damage on -ate abilities has been nerfed. Before I did Galvanize I did other testing and got low-mid rolls that were identical to 1.2x but always missed getting the 1/16 max rolls to make sure of it.
If someone has a set-up where they can test these things at like level 100, please do. I've gone back and forth testing and re-testing, running and re-running calcs, and ensuring that the damage ranges I'm getting are unique assuming the damage formula is unchanged.