What does "detonating mines instant" mean really?

"

Daniel_GGG wrote:

It makes the act of detonating mines instantaneous. I'm not sure in what way we're supposed to have "messed it up".

You would be right, if it really were like this. I've taken that notable passive skill point, and the detonation button still tells me "0.17 sec cast time". You know that 0.17 sec is an eternity: istant means "detonation cast time is 0". Not 0.17 sec.