First of all, you listed 3% QA, meaning you're WSing in Thaumas Coat which is already a bad start. 27% (22% Prosilio) DA and 6% TA since you'd be using Ocelomeh +1 and Toci's Harness.
Even with level 109 mob and 600 defense, prosilio would win anytime you aren't capped on attack.
Taru MNK/WAR with red curries: 154 DEX, 141 STR, 1004 attack, 27% DA, 6% TA with artful +1.
Taru MNK/WAR with red curries: 144 DEX, 150 STR, 1044 attack, 22% DA, 3% TA with Prosilio.
1004/600 - .5 = 1.1733
1044/600 - .5 = 1.2400
Well that's already 5% difference for prosilio, not 3.75%.
Will cap fSTR for both so it's less in favor of prosilio.
((99+13+130)*5.0625)*1.1733 = 1437
((99+13+122)*5.0625)*1.2400 = 1468
(242*6.0625)*1.1733 = 1721
(234*6.0625)*1.2400 = 1759
(242*7.0625)*1.1733 = 2005
(234*7.0625)*1.2400 = 2049
(242*8.0625)*1.1733 = 2289
(234*8.0625)*1.2400 = 2339
(2289*.0036)+(2289*.0152)+(2005*.0412)+(2289*.0152)+(2005*.0644)+(1721*.1742)+(2005*.0412)+(1721*.1742)+(1437*.4709)=
1648 for artful +1
(2339*.0036)+(2339*.0124)+(2049*.0440)+(2339*.0124)+(2049*.0428)+(1759*.1516)+(2049*.0440)+(1759*.1516)+(1468*.5376) =
1656 for prosilio.