Hmm, personally I believe that "how golem moves" depends a lot on its core structure, style of build and main power foci.
Take some crude earth golem for example. It's made out of rocks, sand and mud. Mostly you could think that pilot requires some earth affinity or very powerful earth foci to move it, as it's movement is just controlling the ground and earth that holds rocks. In other words, it's basicly a very large spell that just doesn't break down when you end your concentration.
On other far side, we have the "high-tech" golems that are made out of metals and have clear armored look in them. In these cases, it seems most logical that they utilize similar mana systems as smaller golem equipment, from raider masks to biogolem weaponry. You flow a certain kind of mana wave into joint or "muscle", and it moves accordingly.
There comes the question "why they need the armbands to lock them in?" Answer has two points: one, they lock the pilot in spot so that the mana flow isn't interrupted even if the golem shakes, and two, they allow "Power rod effect" to step in.
Power rod effect: as we have seen up to this point, Drow have tendency to use their hands when controlling mana, even if they are forming a bubble shield or similar non-directional spell. As many might know, controlling the direction of any energy in general is hard in itself, be it movement, lightning or sound. Unless we add something to direct the energy with. Mana is no different, and thus adding anything to conduit it trough makes it easier to control, as it is automaticly given the direction it needs to go into. But, as conduit changes, so does the energy flow. Even minimal changes in conduit alone can cause drastic changes in the energy flow.
Now, let's imagine Drow's hand as a conduit to mana, with palm open and straight forward, fingers together. It's simple flow. Then, let's split fingers apart. This causes dramatic flow change as one becomes five. Bend one finger, and one of the flows changes direction a bit. And so the part continues. These minor microchanges are, at least in my mind, what some delicate controls use. Of course, as you still have limited movement range with hands, controlling everything freely with them alone is a draining task. This might the main reason why there exists co-pilots: they take care of some of the joints and limbs in similar fashion.
Now, one-manned golems are bit tricky with this theory, as imagining you to control both arms AND legs with your arms alone sounds impossible. So, we add up the "willpower", the original mental image needed to cast a spell. It is proven that drow CAN cast spells without hands, it just seems a bit tougher or draining. That is understandable, because to control energy without conduit you need more energy. This might be a reason why Ariel was so drained after practice...
The foci in this theory is, well, a battery. It is simply meant to amplify the faint mana flows pilot causes, as creating enough mana flow to actually activate that size of mana machinery would drain you nearly in instant.
Now, here's some thoughts of mine, written down near midnight just before falling asleep. Hopefully someone catches something out of it...