I had the SAME problems... when you are in the air, you feel like you are doing everything right, but when watching video, everything is different. I'm not that great of a vaulter myself, although my teammates were awesome (buddy jumped 15'+ his senior year).
My suggestion would be to videotape yourself jumping, then taking the time to just see what kind of positions you are getting in. I think my year hiatus does some good because it gives you a lot of time to reflect on the things you were doing wrong.
Some pointers I told myself recently for this season...
1) DRIVE... get horizontal and get the pole bending so it'll give you enough time to get inverted and push. Back in h.s. I don't think I drove horizontal enough, which resulted in the lack of time to properly get inverted.
2) Make sure your arms are extended/locked during the drive, if you bring them in, your center of mass switches from the bottom (hips) to your shoulders taking away the energy that would have been transferred into the bending pole.
Thinking about it now, when you jump staying in the extended/driving position until you feel the pole is bending back up. When you do, start swinging your hips into the inverted position and then collapse your arms. Back in high school, I would swing permaturely which resulted in almost NO pole bend. A fun drill for this is to just jump, but don't get inverted at all, stay in the driving position until the pole snaps you back into the pit.
I'll ask my teammates for some more pointers.