I have never needed to use my valve in any way other than fully open, allowing gas to dump without assistance. I have never needed to manually push it to dump nor have I ever needed to tighten it down due to too much gas escaping. The less gas in the suit, the better IMHO.
I guess there is the possibility of needing to tighten it down if there were a wing failure with full tanks but that is about all I can think of.
I guess there is the possibility of needing to tighten it down if there were a wing failure with full tanks but that is about all I can think of.