Think the Increased Titan Flames nerf is Too Much? Here's the Math.
This chart is assuming perfect conditions for all weapons, excluding secondary effects. This means it is, for example, assuming the Pyro user is perfectly timing their weapon such that they fire up until the last possible moment before they overheat, but not adding the extra damage that Ruiner and Oxy get from DoT and Freeze, respectively.
We can see that Pyro performs so poorly that the highest damage weapons (Ruiner, Evora, Vajra) can miss two-thirds of their shots and still outperform it. And yes, this is including the nerf to ASGs. We can also see that both Tumultus and Oxy - two weapons that I'm sure you've forgotten about if you're in high CL because their viability is nonexistent - will now outperform the Pyro on raw damage, despite the fact that Pyro has 250m less range than Tumultus and does not apply freeze, unlike Oxy.
This proposed change is mathematically absurd. A nerf of 10%, the previously proposed change, would have put titan flames at approximately the performance of the new titan rockets (equalizer/arbiter) with their damage boost from 300m-600m - so, the flames would perform as well at 0-350m as a ranged weapon would at 300m-600m. Still mediocre, but at least not terribly, unjustifiably bad as it will be after the 25% nerf now. This better be reverted.
If you're wondering why I'm not talking about the overheat change at all by the way, it's because it's irrelevant, no matter what number it is. There is some misinformation about the number meaning the amount of time before you overheat. This is incorrect; the number refers to the amount of time you are locked out after overheating before you enter the cooling phase. However, the magnitude of the number is irrelevant because the main purpose of the number is to just disincentivize overheating anyway, which it performs regardless of whether the number is 2 seconds, like on release, or 1 million seconds. The only change that matters here is the damage, and the damage is getting unreasonably gutted.