Oh well, it was an interesting use of in-game mechanics, but Fan of Knives spec (33/38/0) rogues will be a thing of the past next patch.
Fan of Knives: The damage done by this ability has been reduced by 30%.
Throwing Specialization: This talent no longer causes Fan of Knives to interrupt spellcasting.
I guess this might go live at the start of Season 7 – seems a bit silly for Blizz to PTR this as a separate patch before the next medium-sized update. Blue post here.

Hey Sir
Just discovered your site which is a terrific source of info for PVP rogues.
Just wanted to thank you (from France ^^)
Take care!
Thanks for the feedback, take care also and good luck!