To be honest, I have not observed deep thought being that effective. O_O

Most of life seems to involve leaping into the breach and rising to the challenge of the unexpected complications that come your way.

I would never say that planning is unimportant (the good Lord knows, I am a PLANNER, to the point of having had to teach myself spontaneity...!), but the truth is... you can only ever plan so much of your life, and even the parts you plan rarely work out the way you intend. :)