Thanks gwagan. I think Giambrone would agree with what you wrote, based on my recollection the lesson I took. What leaves me wanting through is I can try to shoot that way, but when I miss how do I know what I did wrong or where the shot went?
Well that's the hard part isn't it
It's going to completely depend on you, if you have access to a good coach or even another skilled and proven shooter hopefully they will be able to see your mistakes and help you correct them, you still need to have the fundamentals down and some level of natural ability, though this varies as to what you want to achieve?
If you are lucky like me, if you have an analytical mind, an obsession for skeet, and a healthy dose of natural ability you might be able to figure out your mistakes by yourself, plus after five or six years shooting I took a bender clinic.
Some of my greatest improvements have come from off the skeet field, simply by just thinking about what is happening and what has to happen. Many a time early in the morning kneeling between two cows switching a milker I have had "skeet revelations" lol.
I took three or four years off from competitive shooting and but never stopped thinking about it and came back last year like a house on fire, at least compared to some of my previous performances.
I never really believe in setting goals, they've never affected my day to day life so why would they help in skeet, but in my comeback year last year, I set goals for myself met and exceeded them, I think it helped keep my mental focus on track.
Sorry for the long loopy story, back to your problem of being able to tell what has gone wrong. The first is how do you feel after the shot, and I don't mean happy/sad, I mean are you off balance? is your head off the gun? are you leaning back or to one side? This will give you your first hint.
After a lot of shooting and as bmcrae likes to say "the first 100,000 targets are the hardest"

You will be able to "tell" where your shot went, it just takes experience. Focus on your targets, are you breaking off the fronts? the back end? the bottom? This will obviously let you know if you are in front, behind high/low
I took a lesson from LP as well and I felt I didn't come away with anything helpful, where as I found bender endlessly helpful as to the improvement of my game. I think LP is a better coach for beginners, but not as good a problem solver for those who either have years of bad habits that needs undoing or more experienced and successful shooters who just need some fine tuning.
I am sure he went of eye dominance issues with you, gun fit and those kind of basics. You really need to have those down before you can move forward from there.
I didn't think gunfit was very important earlier on, but now with experience and proper fitting, the difference is absolutely amazing and gun fit is absolutely critical, the tiniest of differences to your comb can make all the difference on the field. A morning spent with Klaus Hiptmeyer really opened my eyes, which were widened further when I got home and was effortlessly grinding targets.
Skeet is simple, remember the basics they are the key to success, the more complicated you make it the more difficult it's going to be.
If anyone wants help send me your phone number or if you find your way to Kingston,ON I'll give you all the free help you want.