[Qiang]

Well, I'll take a stab at this. I think what Ashe means is the establishing the spinning force of coordination is not itself the reason you can harmonize with your partner. Rather, what allows you to harmonize with your partner is being present and in the moment. It's the ability to direct your mental attentions (i.e. mindfulness) that allows your harmonize first yourself (establish the body awareness for the spinning force, absorb-project, etc) and then to harmonize with your partner.

If you lose the mindfulness, you are no longer in the moment. You lose your ability to perceive your partner's energies and also can no longer unify your body to harmonize with your partner's force. Consequently, you feel like you're just a step behind during the partner interactions.

It's not the most well-worded explanation, but hopefully I'm not egregiously wrong.