I would like to assure you, John, that you can beat your target panic. I think there are many paths to success, but Joel's is certainly one of them. If you listened to the podcast, the moderator who took Joel's course talked about his ups and downs after finishing the course, until he got to the point that he made the commitment to himself that he would never again shoot an arrow that was "good enough." It had to be exactly according to his pre-planned shot sequence, or he would let it down. From your comments above, I don't think you have made that commitment yet. Good enough is not good enough when it comes to defeating target panic. Defeating target panic is sort of like recovering from being an alcoholic: there are no grades like A B C & D, and you can feel pretty good if you get a B; there is only pass and fail, because if you leave any room at all for target panic to wriggle back in, it will.
So if you decide to take the online course, I recommend you look at what Joel says not so much as suggestions, to mold your own cure loosely around, but as commands written on a clay tablet and handed down from above, to be done exactly to the letter or not at all.
So yes, now that I've read your responses, I think you could benefit from Joel's course, but only if you commit to it entirely.