mcirishman57 asked about details that might make a difference. I have been working on one that I have not been consistently achieving and is I think resulting in pulls when I don't. That is the 'drop' onto my lead leg.
Scott gives details on this in
Ask Scott #39 and
Ask Scott #85. In #39 he gives a specific warning about tensing the calf muscle of your lead leg which would cause you to have more of the weight on the front of your lead foot instead of evenly distributed over your whole foot. This and sometimes straightening of my lead leg was my problem. The symptom was my ending the swing facing left of target with the ball headed exactly the way I was facing. When holding my finish position I would notice either a straight lead leg or a flexed lead leg but with my foot rotated and the weight on the ball of my lead foot (not distributed).
Right click and download to your system the following clip of Scott and view by alternating frames.
Focus on his lead leg. I was struck by the complete stability of his lead leg and foot through impact. You can just see that the axis of rotation of his hips is at the lead hip as he's noted. This image of the lead leg and hip anchoring the rotation was what I wanted to achieve.
I used the Nike 'fix' (Just Do It) and noticed immediately the stabilizing effect on rotation through impact. The feel I needed to insure this was that my lead foot was 'soft' and fully 'connected' to the ground. This means having my weight on heel, ball of foot and instep. A good check point was whether I could feel the contours of the ground through that foot. I seldom lost it after establishing the 'feel' but the problem was not insuring to establish it before swinging. Finish position when well anchored left me feeling the close contact of my lead foot to the ground and my lead leg 'actively' flexed. In other words not only supporting my weight but still 'athletic' vs stiff. And my lead foot did not move during the swing. This is the kind of thing that will tire you after a while if your lead leg is not prepared for the work.
This is one of the things I was working on when I began to be able to see the ball go through the 'gate'. I don't know if there is a connection but the flexed lead leg is clearly a necessary element of IMA. One of those detail to insure you're doing if you're IMA.
Peter