3.3 Arms ArP (I am bad at Math)

Hello! I was gone from the game the past 2 months and now 3.3 is here and have reconnected with my old 25m which is in ICC 25 (I believe up to Saurfang.)

Since obtaining the Needle I've been feeling like I could begin to gem for strength a bit (Armory) but when the Needle procs I sit at 99.37% (might be a higher decimal, 1397 ArP with Proc.) Passive I sit at 719 ArP (51.37%)

My concern lies in my forgetfulness; the numbers in the stat sheets do not take into account the 10% bonus from Battle Stance nor the 2 piece bonus from T9, do they? if that's the case I'm over the 100% cap, but are those things multiplicative or additive? (math is far from my strong point, thus why I am here)

So, how much ArP can I re-gem as strength without going below the 100% 'soft cap?' (with proc)

Thank you in advance.

battle stance and the 2pc t9 bonus are not added into the arp shown on your character sheet.

ArP Caps:

No battle stance = 1400 (with GT - 788)(with Runestone - 735)(with NES - 722)

Bstance = 1260 (GT - 648)(Runestone - 595)(NES - 582)

Bstance + 2pc t9 set= 1176 (GT - 564)(Runestone - 511)(NES - 498)

Bstance + mace spec = 1050 (GT - 438)(Runestone - 385)(NES - 372)

Bstance + mace + 2pc t9 set= 966 (GT - 354)(Runestone - 301)(NES - 288)

Thank you so much for that!