indeed stamina is very important, when i make love i use Spiritual energy, i still learn this, i focus my attention to my girlfriend and not to chase a orgasme. most of the time i make even love without a orgasme. now i gone to start (learning) "Taoist Sexuality" It's an ancient secret doctrine taught the chinese warlords, channeling sexual energy to heal you. Most men don't grasp this because they do not understand it. In the begin I also had a lot of resistance but I am an open mind. bless you