Q: Does distraction cause us to skip to the next step in a motor plan?
A: It depends on the processes in progress, characteristics of the subject and characteristics of the signal to produce interference (based on an orientation reflex that is the beginning of an act of involuntary attention), many factors, mainly:
Characteristics of the process involved in the distraction (mainly nature of the stimulus but also what relevance it has for the subject).
The nature of the processes that are being executed in the motor plan (automatic or controlled, these processes differ in practice, memory, difficulty, relectivity, required level of effort, etc.) (processes related to sports can be automated much from training).
Characteristics of the subject (different capacities of selective attention, etc.).
See: Shiffrin, R. M., & Schneider, W. (1977). Controlled and automatic human information processing. Perceptual learning, automatic attending, and a general theory. Psychological Review, 84, 127-190.