Well, as someone that't played through the DLC 3 and whole game on difficulty 9, I can say that without this you can expect countless hours of grinding. Since every stat to the MAX which is about 1099998 is still not enough to easily pass through the DLC on Difficulty 9 by a long shot.
Ok, first that's diff 9. There's no reason to do diff 9 besides the challenge and if you are cheating then you obviously don't care about the challenge.
Second, the max stat for hp is 1,099,998, but for other stats it's only 109,998. That's about 30 runs of ignited. Ignited only takes maybe 5 minutes, maybe a little more when you start, which means less than 3 hours of grinding. Hardly countless
Third, you don't need max stats to beat dlc 3 on diff 9. I did it with around 40k stats. You could do diff 0 with probably half that which means less than an hour of grinding.
The thing about dlc 3 is it throws a lot of attacks that do a percentage of your hp at you which means your stats mean nothing. I think every boss except the unicorn and lion have at least one hp percent attack. Heck, even the basic enemy winter knight does 50% hp damage. Additionally, God's fish also does a 100 percent hp attack, except you can evade it. Yes, it will actually one shot you if you don't evade it. On the other hand, its only undodgeable attack does crap damage, so if you build your gear to have 100% evasion and a bit of defense and hp, it's a trivial fight.