Message to User:
I thought about giving you 1 point for each superfluous period but then realized you'd be banned for eternity. So, I compromised with the title. Your post is formatted horribly. Though we understand that not everyone is a native English speaker, the post must be easy to read in order to lead to any meaningful conversation -- which yours isn't.
A few easy things to fix:
-Use one period
-Capitalize the first letter of the first word of a new sentence and the letter "I" when referring to yourself
-Lowercase just about everything else
Why do you say "unneeded expertise". Unless you really cant find a way to get rid of expertise (which agreed can happen, but is mostly a temporary state), the worst that can happen is that surplus expertise gets converted to mastery.
In case of those boots (assuming 40 str socketing, and 20 str 20 hit socketing - i chose the latter because for a lot of setups you need the hit, or can reforge it to crit somewhere, and if you cant then its very close - you can make own math for 40 str socketing !). Reforging i go after my own with mastery reforged to crit on massacre ones.
Massacre Threads MTB
Now assuming crit = 0.65 and mastery =0.4 of str roughly according to simcraft that ends up being around 171 exp vs 11 STR. If the expertise is REALLY useless and you cant reforge it off, then true the MTB can be better. But even reforging to haste at 0.2 SEP, makes Massacre Treads better.
Sinestra neck is certainly better then Nefarian one, its not that clear cut over Alakir. It definitely is a better choice then boots simply because of added socket and higher item level (not the case if we talk about boots). But even then the math ends up being :
+55 STR +128 Mastery +55 Crit vs 143 Crit 143 hit.
Assuming that hit can be generally converted to mastery on your gear we can shorten it to
+55 STR vs 88 Crit 15 Mastery
at 0.65 Crit SEP and 0.4 Mastery SEP its actually 8 SEP behind Alakir neck. I can imagine some setups where it would be better though.
Still its an ongoing myth about sinestra neck being so good - mostly from the time when only other choice was nefarian neck (which in this calculation would be 55STR vs 103 Mastery which is clearly better for Sinestra's).
Shaa...My thoughts are backed up by playing around with all BiS gear in current content....no going so SIMCRAFT precise into it in my thoughts, although i Keep the knowledge in the back of my head, I will say again that, in BiS gear, the expertise from Massacre Treads is not needed if playing around with reforging keeps you at 26 exp....I NEVER gem for 20 str 20 hit, since strength is our number 1 stat and we can only get it from gear and gems hence I gem everything 40 str apart from helm and chest due to socket bonus....all other gear 40 str is best and you can assure hit cap and Exp cap from gear without needing gems. Also I reforge mastery into crit if I need the other stat in a piece of gear and overall you can have a look at my current gear to get the idea of it. Playing around in BiS gear in chardev with my way of thinking, I get about 16.25% crit | 10500 or so AP | hit at 8.02% | 26 exp and 14.14 exp with cloudburst ring of earthfall sinestra neck sinestra ring. I cant recall how to link a fixed chardev character but if you can instruct me I ll post you my thought as BiS picture for Arms in current tier