90 RDM for 30% Fast Cast + 30% from Revelations/MM/Ambition + 22% from Warlock's Chapeau +1/Duelist's Tabard/Loq Earring = -82% Fast Cast, but only -40% Recast.
Weakened Reraise was 72 seconds (-40%) instead of 70 (-41%).
Without Loquacious (80% Fast Cast), Weakened Reraise was still 72 seconds (-40%).
Looks like there's either an 80% Fast Cast cap, or a 40% "Fast Cast's Contribution to Recast" cap.