More important than looking at success by GPA is looking at striving to reach your potential. If you have to work hard to make it, it will likely mean more to you than somebody who skated by. I think everybody "pays" at some point. Sometime during your time in the service, you will reach a point that challenges you beyond your expectations. Meeting these challenges is what separates the men from the boys. To say you'd rather have a bottom guy over a top-performer in the pipeline is nice, but I think we'd all like the guy who can handle stress and complete his initial quals without any drama. Like Co60 said, being a top half guy opens more doors faster. If you're capable of being top half and you're not, ask yourself why not?