Indeed. The paper has references, one dating back 70 years.This has been known for thirty years.
Effects of Cable Loudspeaker and Amplifier Interactions - Fred E. Davis
Reprise of the above paper in Audio magazine, July, 1993.
It has, at best, minimal effect if cabling of sufficient gauge is used over distances of ten to fifty feet.
REFERENCES
Augsperger, “The Damping Factor Debate” (1967)
Floyd E. Toole in “Damping, Damping Factor and Damn Nonsense” (1975)
Richard Clarke “Damping Factor” (2000)”
D.J. Tomcik “Missing Link in Speaker Operation Parts 1 & 2” (1954)
Johnson I. Agbinya “Principles of Inductive Near Field Communications for Internet of Things” (2011)