Sorry,
But I do not see how you keep misjuding left turns, if this is the case you are either ignoring the advise of the instructor our you are mentally switching off.
Reference the Arctic/Wag & Drag debate this has been done to its death, I learned in an Arctic so I would say them but Draw bar do have an advantage of sorts.
Why do you keep taking ti that wide, if you look on the DSA website I think it gives lists of the test routes from each centre. Get out in your car and have a drive on the routes then see where you are goig wrong.
Good luck and dont give up will be worth the stress in the end
Disco