Something related to this assertion has been in the public domain for some time now. I think it is something that is simply not applicable to everyone, presumably, due to hormonal differences. Hormones play important role in the body functioning especially the rate of recovery of strained muscles. And from biological perspective, these hormones could either be quick or slow to secretion after each exercises done depending on the individual's body.
However, personally, after my workout session, I find it quite difficult to repeat the same exercise the next day. And if the exercise is repeated the next day, I will become too fatigue that recovery rate of my muscles become impossible within short time, and it could lead to sickness.
Conclusively, this reduction of fatigue induced by repeated exercises work specifically for particular set of people. It would be out of place to generalize the practice, because doing so might leave some in harm's way.