Shadowy Insight occasionally bugs out

[seanpeters86]

Game Version:
10.0.2 live Build 46741

Description:
Sometimes when casting Mind Blast and getting a Shadowy Insight mid-cast you will consume a charge of Mind Blast, but not consume the buff of Shadowy Insight. Doing so can put you at 0 charges but still with the buff active, but Mind Blast is not castable.

Details:

Try to explain the bug.

Logs, Images, Videos
TBD

Reproducible:
Hard to do consistently

Howto:

1. Put up Shadow Word: Pain
2. Cast Mind Blast, but cancel before it goes off unless you get a proc