I never said NOCS affects spells.
No it does not work like that
MH hit cap is exactly 8% I'll give u a picture below,OH is 27%
Yes HB,BB,DnD,ty for adding them.
You don't really need to reach spell cap since you'l lget another 6% hit and you could chain Pestilences if you're that worried that you'll miss or you can use pestilence,before Blood strike or w/e else you're using,there's no need for that cap.While autos are indeed your 2nd highest dmg improving OH hit instead of your total dmg done via Str /arp gems will be a waste since Oh doesn't hit that hard(75%).
The pictures as promised
test on MH misses(300 hits 5,25% hit,total hit 8,25% with talants,no other buffs debuffs on target except my own):
http://i.imgur.com/uUwNrcT.jpg
My normal dps and rotation gave me this result with 6,83% hit,9,83% total same buffs and debuffs as above.
Melee:
http://i.imgur.com/FbrBnG9.jpg (there are misses only from off hand,obviously)
Obliterate :
http://i.imgur.com/2hjhnw0.jpg (only parries since parry cap is 56 expertise)
Howling Blast :
http://i.imgur.com/6OUII7A.jpg (1 miss due to lack of spell hit cap)
I can't upload a pestilence,since it doesn't do any dmg thus it's not up in recount,I do miss it from time to time but as you can see that can be worked around,escpecially in a raid envirenment.
I will do 10m dmg if need be,but I am positive that 5% + another 3% from talants are enough for you to cap on specials + MH autos which I find to be a bigger dps gain than to go for a full cap on spell hit + OH hits.