Oct. 11, 2018-Empirically speaking, inter parental conflict in itself should not negate joint physical custody

... A meta-analysis reported better emotional, behavioral, and academic functioning for children in joint physical custody compared to children in sole custody, regardless of the level of conflict between parents.[citing Robert Bauserman, Child Adjustment in Joint-Custody Versus Sole-Custody Arrangements: A Meta-Analytic Review, 16 J. FAM. PSYCHOL. 91, 99 (2002).

Rather than magnify harmful effects of parental conflict, several studies suggested that joint physical custody may protect children from some of the potential negative consequences of conflict.[citing multiple sources]

Conflict does not erase the benefits of joint custody.

The fact that joint physical custody children had better outcomes even when a parent initially opposed the plan and even when conflict was high suggests that parental conflict has been oversold as the main factor linked to children's postdivorce adjustment. Nielsen found that in predicting positive outcomes, high quality parent-child relationships are more important than low conflict or cooperative co-parenting. And high quality relationships need sufficient time to develop and flourish.

Richard A. Warshak (2017), Stemming the Tide of Misinformation: International Consensus on Shared Parenting and Overnighting, Journal of the American Academy of Matrimonial Lawyers, vol. 30, at pp.196 - 197