"Don't believe a thing is true just because some famous baseball player says that it is." -Billy Beane
Just because someone is world renowned or in a position of power doesn't mean they are correct.
Two sayings. Both correct. Don't just readily accept some experts opinion because he is labeled an expert. That's my advice for the day.
Just because something is written down or in a book or on a video don't think it's absolutely correct. This is one of the most important things to learn when you become a coach or read training articles. Be critical of everything you read.
One of the worst sports that these quotes apply to is baseball. Baseball is so heavy set in tradition that they do stuff just because that's how it is always done or that's how some great player did it. They are very very slow to change. A good example of someone willing to change is Leo Mazzone. The way he works his pitchers makes a heck of a lot more sense than the traditional way from a physiological point of view (hmm interesting that he consults an exercise physiologist) and the results speak for themselves.
Anyways, just a thought to ponder. You see pitchers warm up in the bullpen. You ever see a pitcher cool down?