I have the very same problem. In lessons I have been told to point my toes in, but in doing it feels like I lose contact with the inside of my leg and my hips lock up. Interestingly enough, at a clinic I went to the other day, the man pointed out a girls toes (which were pointing outward) and asked everyone in the bleachers to stand up (this is something to try at home) First stand with your toes parallel to each other pointing forward. Move you hips forward and backward, side to side. Now point your toes out slightly. Now move your hips around, feel the difference? When your toes are facing outward slightly it opens your hips for free-er (hmm, new word?) movement. (could very possibly be an equitation 'feau-pas' but funny how that works!