Primary instructor Michael J. Crites and professor Jamie C. Gorman of the Human Factors Psychology dept. at Texas Tech University Lubbock, US, have investigated (experimentally) some of the difficulties of shoelace tying – with two hands, one hand, and with someone else’s hand. See: Learning to Tie Well with Others : Bimanual vs. Intermanual Coordination during Shoe-tying in Proceedings of the Human Factors and Ergonomics Society Annual Meeting September 2013 vol. 57 no. 1 1377-1381
“A shoe-tying paradigm was developed to examine mode effects and motor learning functions when people are asked to handle a familiar object (e.g., tying a shoe) using an unfamiliar coordination mode (e.g., tying a shoe with another person). Dyads first tied a shoe apparatus using their own two hands (“bimanual”) for 10 trials and then tied the shoe as a dyad, each person using one hand (“intermanual”) for 20 trials. Finally, participants tied the shoe bimanually for another 10 trials. Previous research has indicated that intermanual is faster than bimanual, but those experiments examined novel tasks performed by novices. For this familiar task, results revealed that participants were significantly slower in the intermanual mode compared to either set of bimanual trials, and participants were significantly faster in the second set of bimanual trials than the first. Unlike mode effects for novel tasks with novice participants, the intermanual mode was slowest, though intermanual performance may have enhanced subsequent bimanual performance. Previous research on motor learning suggests an exponential function describes acquisition of a novel skill, whereas a power law describes persistent motor learning. Analyses revealed that dyads exhibited a power law function over both the first set of bimanual trials and the intermanual trials. That finding suggests that participants were not learning a new coordination skill in the intermanual mode but may have transferred persistent, bimanual shoe-tying skill to the novel mode. Theoretical and practical implications of acquisition of a novel coordination mode for a familiar task are described. “
Also see, a previous paper: Are Two Hands (From Different People) Better Than One? Mode Effects and Differential Transfer Between Manual Coordination Modes in: Human Factors: The Journal of the Human Factors and Ergonomics Society August 2013 vol. 55 no. 4, pp. 815-829