I've never left at WOT. Never had a 2 step. Back when I first start racing, the nostalgia classes would not allow such a thing. I learned to do it the hard way........and 23 yrs later I'm still doing it. Old habits....you know?
I hold the throttle at 5K, 5500, 6K, whatever the track will hold. Then when I dump it, I mash the throttle.
I have a pair of 660's on the blower car, but still not happy with them. Not sure if they are just too beat up? Run okay, but still not right. I tried them on the wagon and got a huge stumble(like on blower motor). Never really figured it out. I have a second pair a friend gave me to rebuild and try. Never have. I have a pair of 735's I converted to single feed and going to try, some day.