Ironically, many other women say that the same problems stem from their lack of height, or small hand size. Go figure.
Your problem (almost certainly) isn't height.
The most common reason leading to poor control of the knife when making the chopping cuts is grip. Even if you're using a pinch grip, if you hold the knife too tightly it will steer. Softening your grip requires a very sharp blade and a great deal of practice. When you're tense or rushing (like every other culinary student in the world) you'll naturally grip hard. Stop.
Another grip problem is a bent wrist. If your wrist is too bent, the blade will veer.
Posture is another problem -- and by posture, I don't just mean standing up straight. If you are standing with your feet square to the counter, instead of having your left foot slightly in front (assuming you're right-handed) the knife will want to veer to the side.
All of this has to do with getting and keeping your knife pointing in the right direction. If your grip is too tight, if your wrist is bent, if you're too square facing the board, the more your knife will angle across your body. The more things wrong you do along those lines, the more you're going to want your face close to the food to make sure your knife is in the right place. Do them right, and your knife will intuitively point where your eyes look.
If you're having trouble seeing what you're doing with very fine cuts, you might want to have your vision checked. You might need something for intermediate distances; like tri focals or blendeds. And yes, vision is related to height.
The silver lining is that even if your grip, posture and eyesight are imperfect, practice will eventually catch up. It takes longer, your skills won't hold up as well under pressure, but you'll get it. Guaranteed.
In the meantime, read Getting a Grip on a Good Pinch. Couldn't hurt, and might help.
Brunoise do not spring fully formed from the board. It's a process. Your brunoise difficulties almost certainly include poorly done "plank" and "stick" cuts as well as with the final dicing cuts. Start right, and at least you have a chance of ending right.
Block your food into lengths you can handle, and shapes which will plank easily. When you plank, get rid of pieces which won't stack right. When you cut your sticks (matchstick-julienne precedes brunoise), don't stack the planks higher than is comfortable for your natural knife action. Don't bundle more sticks than your natural knife action can comfortably dice.
If your natural knife action is "rock-chopping -- with the knife tip always down on the board -- that means fairly low stacks and fairly small bundles.
With your sticks cut, bundle and orient them so the sticks are perpendicular to the natural angle of your knife. In other words, don't fight your body to make things line up to your board. When your bundles start to get away from you, loosen your grasp and square them with the flat of your knife.
If you find that your chopping into a pile of already chopped food, reorganize your board as needed. If you don't, you'll contort your wrist and posture and your cuts will be sloppy.
Clean the side of your knife frequently. Food stuck to the knife face comes off in the worst places and gets in the way -- as described in the paragraph just above.
Take your time on sizing all three of the cuts. Use the knuckle bones and/or nails of your claw hand as a guide for every cut. That may slow you down a little at first, but remember that precision is a product of good technique. Once you start getting thickness right, concentrate on working smoother while retaining your precision. Speed is a product of smoothness, and will happen without you working at it. Rushing is the enemy.
Most student knives are too dull. You can compensate for that, to some extent, with good technique. But, you're not there yet. Keep your knives sharp. Sharper than they came from the factory.
PS. I'm 5' 11" barefoot -- or was before being crushed by the weight of the world's sorrows. I'm not sure how tall I'd be with your Danskos on. They probably wouldn't fit anyway.
Edited by boar_d_laze - 5/5/13 at 7:28pm