In 1988 Carl Lewis lost his focus and lost his shot at a gold medal. Why? Because he let Ben Johnson get in his head. If it can happen to someone like Carl Lewis, it can happen to any of us.
The tricky part of training is when people try to ride two horses with one ass. You can't specialize in more than one thing. Know yourself and what you want well enough and you'll know how to train.
For years I was in denial, but I was "that" guy. The guy always switching workouts and never seeing any results. I finally came to grips, but I think our culture is vulnerable to this wretched malady.
Sometimes in an athletic endeavor, you can’t go wrong. You anticipate next steps and you feel invincible. Like Neo, in The Matrix. This is the phenomenon known as "flow."