Right foot back drill

Right foot back helps create a draw. ( Make a normal  set-up on target line, then move your back foot back a little.  Keep club face on target line, but swing on foot alignment line.)  I think what your coach has done will straighten out the ball flight, but doesn't address an outside to inside swing.  Try this thread maybe to start getting some tips.

.

http://thesandtrap.com/t/10878/glove-under-the-armpit

It should not be an issue b/c you can vary how far your right foot can be back.

Also, I don't think your instructor is suggesting it as a perm fix.  I did that time to time to remind me what in to out swing is/should be like.  Over time, it fixed my out to in swing for good.

I shared this in another post. The pro at my local club gave me a neat tip.  Set up your ball with the logo at the back of the ball on the target line, then rotate the logo 1/4 turn in towards your back foot. Swing really slowly, thinking ONLY of hitting the logo , not swing mechanics, ball flight or target.  Your aim should shift you into hitting inside out without having to consciously think about it.

I had an outside in or over the top swing and this helped me a lot.

A very inside to out swing path can produce a shank because you are pushing the clubhead outward.

Not really a drill that I found successful.

It's definitely not a permanent fix and he said this will help get the feeling but over time I should bring my foot forward once the feeling is there.