I think that you are all being rude and judgmental. People go into a state of "haal" when they are overcome with emotion.
Perhaps, the people that are overemotional are unable to control their feelings are in a dervaish state due to their love of their group or group leaders. There is no jolt or shock involved.
People should respect other peoples opinions and feelings. Its the Islamic thing to do, whether you agree or disagree with something like this.
And no, I dont follow pirs or do anything like above but I have been to zikrs or mehfils where I have seen this typlation. I know people who tell me that te of behavior first hand. I can attest to the fact that peoples emotions sometimes get the better of them.
You can testify only if you felt this way or your emotions got the better of you in this way , otherwise it is all speculation ,guys who pretend to have haal are genuinely in the state of ecstasy should not feel a pinch by a needle and many of my cousins who have been to those mehfils swore that they poked needles into those guys and they immediatly started to scream pain. So in the end it is all drama they play.