I think I'll stir it up a little for you all. Back when I was learning to ski shortline (in the 70's) I would follow what the top pros of the day "said" which was as the line got shorter you waited longer to go, that made me fast and made it impossible to maintain angle off the 2nd wake.
(I also think that back in those days the top pros were all big strong guys, myself being 5'7" 160
could not resist the boat off the 2nd wake with the technique of the day) Based upon observation of top pros I watched it looked like as the line got shorter they would turn in earlier & earlier as the line got shorter. No one said they did this, however it is what I observed. When I tried this approach it worked. (it took me 20 friggin years to figure it out) At 35 and longer I can wait later and still make a pretty good pass. I believe this is because at 28, 32 35 the skier doesn't really generate much speed differential between the line lengths. 38 is the game changer. I now go much earlier on the gate in. I call it "roll in" I start to roll in an entire boat length before the tip of the boat gets to the gate. As I "roll in" I'm free of the boat, the boat catches me at the white water, that is where I really resist the boat. (never adding lean, just resisting) I still fight the urge to want to "go hard" early from the KLP days. At 28 & 32 it feels like I'm literally doing nothing, its really boring to ski those passes and it really does feel good to start harder earlier, however I now know from experience that by "rolling in" on my easy passes I set up the timing for 38 & 39. I also learned something from Wayne Gretsky the great hockey player. He said he was better than everyone else because he didn't go to where the puck was, but to where the puck was going to be. Now the slalom course is stationary and we are moving, we have to always be ahead of the course. By watching video of really great skiers with a video camera on thier head was a real eye opener also because I saw how much earlier they were from the eyes view than myself. It all starts at the gate and going early, a full boat length early is important. Also note as the line gets shorter you will get the angle you need from white water to white water just because the rope is shorter. So GO EARLIER and just resist. Once you get it, it really isn't so hard. (it actually makes slalom easy) Keep all movements to a minimum, a 2 handed gate is less movement, less risk, and the turn in for the gate is a much different turn than a buoy turn, much less speed on the turn in. I know I have rambled abit on this, I hope my observations and experience help some of you to avoid the pitfall I had for so many years of mastering a good gate. I also hope you don't all think I'm too off topic!
To Summarize.
1:Pull out slow and easy, wide enough to be free of the boat pull.
2: Stand up tall in a stack position at the apex with the load on the left arm.
3: Roll in easy, when the tip of the boat is an entire boat length from the gate.
4: Resist the urge to lean or get caught by the boat untill you are at the white water.
5: Once in the white water only resist the forward momentum of the boat. Keep equal pressure on both feet to keep the ski level, bend you knees, and point the knees in the direction you are going allowing your entire body COM to go a little lower so you can keep from getting "caught" by the boat too soon.
6: push the handle low and keep elbows tight to the body, hands close to body
7: Keep the handle control off the 2nd wake (this gets harder as the line gets shorter)
As the skier comes off the 2nd wake they will naturally compress from the trough and the angle generated.
As the skier comes off the white water with handle close, more pressure on the right arm as the skier moves outbound, the skier will start to stand up to a stacked position. This allows the skier to stand over the ski, put more ski in the water on the preturn, and start to ski over the line, (this will create the reverse C position as the ski changes edge and also will look like the "pull up" described by many coaches, moving toward the apex, and getting "free of the boat" at the 1 ball.
If I have put into words what I "feel" and "observe" as a skier on the gate & approach into 1 ball.