It's not the size of your step that matters; It's how you use it. Or so they say. (c:
When teachers talk about faster tempo requiring smaller steps, they're actually only giving you half of the story. The reality is, as the tempo increases, one of either two things must happen: Either (1) your steps must get smaller if your body speed through space remains constant, or (2) your body speed through space must increase if your step size is to remain constant.
There is actually a perfect, three-way relationship between the following 3 things:
(1) Time between steps
(2) Space between steps
(3) Body speed through space
If you fix any one of those elements, the remaining two then become directly proportional. As one increases or decreases, so does the other, and vice-versa. Most of the time in our dancing, the fixed element is #1: Time between steps. The timing of the pattern combined with the tempo of the music dictate the exact amount of time between each of the foot falls. So the remaining two, space between steps and body speed through space, become perfectly proportional. You can either move less and take smaller steps, or you can move more and take larger steps. The choice, then, simply becomes one of ability and preference.
Those who have trouble "keeping up" with the tempo of the music while executing a particular figure, assuming the timing is fixed, must choose between shortening the steps or increasing body speed in order to cover the space that the full-sized steps require. Sometimes for various reasons, your perception of things can trick you into feeling otherwise, but this fact is pretty much an absolute.
My guess as to why nloftofan's instructor asked for bigger steps was to elicit an increase in effort to move more. The size of their steps may have increased somewhat, but if the perception was that it was easier to stay on time (and assuming the perception was correct), the only explanation is that an unintended side effect of the increased effort was an even greater increase in the body movement through space.
Any instruction based on perceptions will always get mixed results, because different people feel and react to things differently. So who knows... It certainly can't hurt to try this method out and see if it helps. If your reaction to taking bigger steps is move your body faster, and your increase in body speed ends up being greater than your increase in step size, then it might just work for you. But if it doesn't, at least you know the reason why. In the end, if you can't keep up with the timing of any particular pattern, you're ultimately going to have to either move your body faster, take smaller steps, or find some happy medium between the two.
Regards,
Jonathan Atkinson
BallroomDancers.com