I know, that was kind of a sarcastic answer.
I treat my plane like a motorcycle. It almost never is below 1/2 tank(s) of fuel. Fortunately, I got to learn that lesson as a teenager when poor fuel management only meant a tiring and embarassing push down the side of the road. My distrust of fuel guages was well entrenched before ever sitting in a plane.
However, I was taught as a student that if necessary you can take off from said airport with the short runway on a hot day with enough fuel (plus at least a 1/2 hour reserve) to fly directly to the nearest airport which is more suitable and fill up. That might be a wiser choice than pushing your luck with the take-off perfomance of the plane. Personally, I've never been in that situation.
