Injury Denial Syndrome seems to track to the following.
The better a player is the more desire fans have for him not to be injured, because injury puts season hopes for success in jeopardy.
Injury tends to trigger sudden, negative impact on a player's performance stats. All sudden change for the worse makes fans fearful.
The higher the hopes for a season the more threatening a potential injury is, and so the more fans resist acknowledging it.
Persons manifesting this syndrome often attack others that draw their IDS (Injury Denial Syndrome) into question by reactively and absurdly overgeneralizing that others see injuries every where. (Note: this aspect of IDS resulted from observations of @Wissox).