"You asked for an exercise. This may sound silly but you could try pushing a very heavy wheelbarrow. This will help because the heavy wheelbarrow will make it impossible for you to move in a choppy way. you will get the feeling of your body moving continuously and smoothly forward while you legs and feet work underneath you"
Phil, this has a kernel of great insight in it.
What the wheelabarrow does is give you a resistance to work against, and encourage you to fully commit your weight and drive into the movement without holding back.
Most beginner and intermediate dancers won't get the opportunity to do that, because the've already gotten ahead of themselves and must try to slow their body down at a time when they really should be driving.
When the dancer develops enough skill to draw out the preceding lowering action, then they will have the opportunity to drive into the next heel lead - instead of already going to fast, they will be needing to speed slightly with an actual drive. Instead of external resistance in a wheelbarrow, the small but critical resistance will be coming from the inertia of pushing to accelerate their own body.
If you feel like you you need to put on the brakes during a heel lead step, well that's evidence that you've gotten yourself moving too fast too soon. There's nothing within the realm of proper technique that you can do to fix it this time around, only try to draw out the preceding step more in the next measure.