I don't think the two have to exist in conflict. We can never know if a route is going to be amazing or if the rock will hold forever, but most of us have climbed enough to make educated guesses.
With limited resources, we need to think about the mark that we leave and the untapped potential we leave for future (stronger and possibly more visionary) climbers. How often, do you climb a line and wonder why it avoids the obvious awesome line 5' next to the choss you are climbing?
What I am talking about is giving the route much consideration from the ground or other vantage points, but if that doesn't give you a clear picture, then give the thing a rap and make sure it is worth it. Also, make sure that what you think will be climbable (higher up) will be. That way, when you start heading in a direction, your line of bolts will actually go somewhere.
Does that make sense?
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And to be clear, I am not talking about TR'ing the thing, only taking a quick zip down and maybe swing left and right to make sure that you see what you think you see.