I start my practices with a dynamic warmup. My dynamic warmup is used as much to teach basic movement skills as to warm up the players. Consequently, I do not use cones, and I instruct players during the warmup.
When I watch soccer teams warm up, I rarely see the coaches overseeing the warmup. It is clear that the players have done the drills previously. With drills such as the jumps over the cones, it appears that the players focus on the outcome – jumping over the cones – and not the process of improving their technique.
Often, the external focus on the task outcome is the best approach to developing a skill or technique because there is not necessarily a perfect technique because of individual differences. However, the task constraints – the cones, the instructions – can create undesirable consequences: The cones, from what I see on a weekly basis, create an undesirable posture, and do not allow the player to develop the desired outcome (improved kinesthetic awareness and body control).
The kinesthetic awareness is knowing how high they must jump, how far they must jump to clear the cone and not hit the next cones, and controlling their momentum in the air. This is important in a basketball game, as a player shoots a layup or jumps for a rebound and has no vision of the ground when landing. The player must anticipate and prepare for the landing with the requisite strength and balance; when a player does not have the requisite tension built up prior to landing or when the player lands off balance, injuries may happen.
This does not mean that the cones are incorrect. Occasionally, a barrier is needed to constrain behavior terms of distance or height. However, when we use something such as a cone, we have to ensure that it does not change the desired behaviors. We do not want to use a potentially beneficial drill to develop bad habits.