sigh
Yeah, I'll do the math again since I don't feel like digging it up.
Level 5, fighter, +4 mod, Greatsword, masteries are the same, fighting style is the same. Assuming 60% hit rate for normal, think the math was 84% for adv
Old GWM w/o ADV:
2d6+14 = 21
21 x 2 x 0.35 = 14.7
7 x 2 x 0.05 = 0.7
14.7 + 0.7 =15.4
Total: 15.4
New GWM w/o ADV:
2d6+4 = 11
11 x 2 x 0.6 = 13.2
7 x 2 x 0.05 = 0.7
.4 x .4 = 16% of both attacks missing
1-0.16 = 0.84
0.84 x 3 = 2.52
13.2 + 0.7 + 2.52 =
Total: 16.42
Old GWM w/ ADV
2d6+14 = 21
21 x 2 x 0.59 = 24.78
7 x 2 x 0.0975 = 1.365
24.78 + 1.365 = 26.145
Total: 26.145
New GWM w/ADV
2d6+4 = 11
11 x 2 x 0.84 = 18.48
7 x 2 x 0.0975 = 1.365
.16 x .16 = 2.56% of both attacks missing
1-0.16 = 0.9744
0.9744 x 3 = 2.9232
18.48 + 1.365 + 2.9232 = 22.7682
Anyways, it actually doesn't give a damage boost slightly better than flex.
New GWM is +0.8 with a single normal attack levels 1 thru 4, +2.52 with two attacks 5 thru 9, +3.744 with three attacks 11 through 15, ect
Flex (not typing all the math) is +0.65 with single attack 1 thru 4, +1.3 with two attacks at 5 thru 9, and +1.95 with three attacks.
I mean, sure, levels 1 thru 4 it is a difference of .15 which is small, but that quickly rises into being nearly double the bonus by level 5 and staying there. And if you don't account for the scaling number of attacks, say you are looking for a paladin, then the flex bonus remains a +1.3 and the GWM bonus tops out at +5.04