I have never owned a welder with 4T, but I have seen the diagrams of how it works, and I think I basically understand them. Press the switch to initiate the arc, release the switch to begin upslope. After upslope, the welder holds at the welding amperage. Press the switch to initiate downslope, which plateaus at some low amperage. Release the switch to break the arc.

What happens if, during upslope, you press the switch again? Does the welder go straight to downslope?

Presumably if, during downslope you release the switch, the arc goes out immediately--right?