Useful nade for when you have trouble fighting for mid control as T.
Makes visibility from Z window extremely hard, and nearly impossible from Z door.

Boost Teammate into position and have them wait.
Back up to barrel and throw at the strut.
Let the boosted player do everything else.

I don't play Cache often, but this nade seems to be half decent for taking mid.
Works better in my experience when either the smoke player flashes for boost, or if you peek in tandem with someone in T main.