I think that this song uses different aspects of driving as an analogy to life. The first part of the song says that dwelling on the past can be a major distraction ("you got one eye on what you knew"), while you're trying to do something new with your life ("and one eye on what you do"). Another line that talks about the perils of indulging too much in the past is "So be careful when you're walking in the view" where "view" really means "rear-view mirror" - a mirror into the life that has gone by. Chris Martin then switches gears and assures his lover (I assume that who he always talks to) that no matter what the "road" ahead (i. E. The future) looks like and what the dangers ("crocodiles"), he will always have "one eye on the road" (challenges of the future) and "one eye on you" (love/care for her).