1.08 removed the 300% cap.
Here's an article describes that. I believe I saw that in official release notes too.
Magic Find & Gold Find Cap at 680% in 1.0.8
There are multiple increases in patch 1.0.8 to the Experience, Magic Find, and Gold Find that can be obtained. Vaeflare detailed just how this will be changing, and how the Gold Find and Magic Find bonus can reach 680% in the next patch!
They never removed the gear/paragon magic find cap of 300. If you have 307% via your gear and paragon levels, you are only getting 300%.
From the article you linked me:
"Starting in patch 1.0.8 however, the Magic Find bonus from shrines will be able to exceed the “soft cap” of 300% that players can achieve from a combination of their own gear and their follower’s gear."
"So after patch 1.0.8, if you have 300% Magic Find from your gear, have 5 stacks..."
Yes your magic find can reach 680% in MP10 with 3 friends and a magic find shrine buff, but your gear/paragon magic find maximum is still 300.
10/18/2013 05:12 PMPosted by LylirraAwesome! Love all the changes you've been making and excited to see how the site will grow over time. Great work. :)
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