From what we have learned in the past, this statement is not totally true. Supposedly every injury has a certain grade level from say, 1 to 10, 1 being the lightest and 10 being the most severe. Every grade-1 injury allows the player to return by the next game, while every level 10 will mean time off regardless of the skill level of the doctor. Time off for injuries between those two grades will depend on the doctor's skill level. For example, a grade-3 injury might mean a one-week layoff with a level-1 doctor, but no time off for a level-4 one. Likewise, a grade-8 injury would mean a 3-week layoff for a level-1 doctor, but only a 1-week for a level-5 (these examples are only estimations)..I hope that this helps clear up some confusion about the skill levels of doctors...
Pappy