Watched the video,which is basically a run through of the NSRA training course manual for club instructors,any club instructor,of which I am one,would be far better placed to improve your shooting,a training programme needs to be tailored to suit the shooter,it's not a one size fits all kind of sport.
To give you a good example,I am currently training a young shooter who is left eye dominant,but insists on shooting right handed as her left arm isn't strong enough to hold the pistol for more than 7 shots,the options are,
Learn to shoot left handed
Use a blinder to train her to shoot with her right eye,my preferred choice!
Use a canted grip
Give up shooting,and concentrate on strength training until hold is improved with left arm
Hopefully this emphasises how personal your training needs to be
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