Please don't @people, this isn't twitter. Your post is more easily understood if you quote a person and then respond. If it's the same person, don't multi-quote, but for different people it's entirely fine. Thanks a bunch.
The catch with SMF and the Madness of DW proc weapons is that Slam hits with both weapons for SMF. Hence the theory of TG about Gurthalak does not stand for SMF, so for it, I would say all hits can cause a weapon proc if we go by the common belief that, BT procs it even if its in OH and RB procs it from OH attacks and HS procs it even if in OH.
For spine I tried all possible combinations of Fury specs. Went
TG high hit (20%) low mastery (7) & low crit (20%)
TG low hit (12%) decent mastery (9) high crit (29%)
TG non cap expertise (25) decent mastery (10) decent crit (26%) decent hit (17%)
SMF High Hit (21%) average crit (21%) low mastery (6)
Out of all these, the most stable results came out of
TG non cap expertise (21) decent mastery (10) decent crit (26%) decent hit (17%)
which allowed me to have a rather low rng-related, decent burst to the tendons (average of 1.3 mil per tendon phase or 2.5 per armor plate) as well as pushing very good numbers on the amalgamations, being amongst the top on dmg there too.
Hands down, Arms is far better for Madness. Every aspect of the fight on heroic leans in Arms favour. Be it the aoe of Regenerative bloods on top of parasites with the addition of B & T for rend aoe, pushing spellweave damage through the roof, be it cleaving the Mutated tentacle on the back while dpsing the parasite with sweeping strikes active, be it the high execute uptime both in each platform and on last phase, or even for bladestorming the congealing bloods in the last phase to kill them asap as well as again using B&T to max rend aoe and hence spellweave damage on them, and lastly even for dpsing the Blistering tentacles in platform 3 and 4 (when there is no Alexstraza fire breath to kill them) while using sweeping strikes to also dps the arm or wing tentacle, anyway you see it really, Arms just trumples over fury. the only benefit of fury would be deathwish during under 20% on each platform, yet with execute dealing 30% extra damage as arms, even then there is no big difference if any at all.