Since noone in game is answering tickets, I will write it here.
Between Blade Storm activation and hit is really large delay. After combat log analysis found out that this delay vary between 0.4 sec on best average to 0.9 sec to worst average. This is an issue especially when you try use precision slash buff window to its fullest by using 4 zened blade rushes and 1 bladestorm at the end. Sometimes you hit it in time, sometimes not.
I also compared it with Marauder's Force Scream. This skill is noticeably faster, average time between activation and hit is under 0.2 sec.
Please try to mirror your classes bioware :-)
Thank you, John.