I'm scratching my head wondering the same thing. I suppose if you wanted 4T behavior but *wanted* to have to hold the button down? But that would be something different than 2T ("enhanced 2T"?).
I wouldn't expect 2T to ramp up/down, and in fact I know a guy who managed to get his welder into a mode like that when his pedal was plugged in, and the ramping + pedal control = chaos. So, I don't see it as a good thing in most cases.