Wrong. When you factor it into your maths, it becomes a maths problem. [Data Entry problem is more precise.]
Wrong. Weapon I guess, sounds like you confused Greatsword and Greataxe. [As I stated, so just redundant and repetitive.]
Wrong. Since we need to compare it to TWF damage, not just it's own damage without the -5/+10.
Wrong, an Action Surging Archer applies the +2 seven times. An Action Surging GWF applies his feature 6 to 7 times. An Action Surging Duelist applies his feature 6 times. An action surging TWF applies his feature... once.
[So I finally caught onto what you were on about here as I was already considering Dual Wielder vs GWM/SS. Dual Wielder applies the bonus 7 times (d8 vs d6), so yes without DW TWF FS gives its feature only once. Still not sure how you are getting 7 attacks with an Archer or GWF. Multi-attack gives two additional attacks at 11th level. Action Surge gives an additional action, so 6 attacks total plus the Bonus Action. I only see the Samurai Rapid Strike feature allowing that -- but that would also apply to TWF.
Wrong.
Wrong. You only included high numbers, rather than "exceeding 75%".
Wrong. Three years of maths. I didn't spend three years learning how to perform exactly one operation. [*mathematics, though it is possible you spent three years repeating the same course.]
Wrong. I need a life.
Wrong. We're doing more than one operation, therefore we are doing maths.
Wrong. I could do that by the middle of primary school. [Sure]
Wrong. I am all of the chill.
Wrong. It is about many different games.
Wrong. And I wouldn't make an entire post just to invest more into it.
Wrong. That is what's happening.
Wrong. Which I shall prove when I get around to doing the -5/+10 for GWF.
Wrong. It definitely seems to need a boost given how often that comes up.
So none of the above was helpful in making your point. I rebuilt my spreadsheet and graphed the data. I think we are mostly in agreement here.
TWF with the Fighting Style and Dual Wielder are competitive for Tiers 1 and 2. However, by Tier 3 Great Weapon Master and Sharpshooter just outclass everything. Even in Tier 2 they have a large advantage at mid- to low target ACs. These feats probably need to be -5/+5 instead of -5/+10.
Since TWF really needs the light weapon restriction removed. It probably should just be made part of the Fighting Style; this would also address your concern about TWF not getting its bonus applies during an Action Surge.
For TWF to be competitive with GWM and SS, I am also of the idea that the Bonus Action restriction should be lifted -- probably could be incorporated into the DW feat.
Without GWM and SS, TWF w/DW mostly falls inline with expectations. GWF does the most damage, then TWF, then Dueling, then Archery.
What might make TWF appealing to classes that don't get fighting styles and/or multi-attack would be to allow TWF with a one-handed weapon and a light weapon as the default instead of just two light weapons. I need to mess with my formulas to see if that would be feasible.
I have been running 5e for about a year and half (almost all on Roll d20). Only at this point did I really decided to take a deep dive into the numbers. Mostly because my players are not the optimizer types, they just like to play the game with the character concept they like. However, last session a paladin character was fighting zombies and not using his GWM feat. I felt he might need some guidance about when GWM was a better choice than not using it, which is why I care about the inflection point and was trying to find a simple rule of thumb he could apply.
I also wanted to test some house rules to make sure that they didn't disadvantage anyone greatly.
Finally, you are incorrect about the usage of math. It is either math or mathematics -- maths is clearly wrong. (i.e., "I am working a math problem." or "Over the years I have taken a number of mathematics courses.") It doesn't matter how many mathematics disciplines one applies to a problem it is still just a math problem. Of course anyone with a brain knows that British and American English forked in the late 18th century (the Brits decided to double down on the French influence), so we all know these are just regional differences so deal with it.
