I found that random searches sometimes gave me the same results several times. That means I'm scanning the same keys more than once!
What size search range were you using? It must have been a somewhat small one relative to GPU speed.
Imagine a big bag full of green beans and only one red bean
By not leaving the red beans out after grabbing one, on average, you double your attempts. Meaning, if you place the red bean back in the bag, you will find the green one, on average, after 100 attempts. By leaving the red bean out of the bag, you would find the green one, on average, every 50 attempts.
If people like mcdouglasx, alberto and zielar approve of this topic, I can show you a small presentation example.
Why do you need approval of these people lol?! It is a community forum, post whatever you feel like, as you already have. Why not include ktimesg's name as well? Because he doesn't agree with you 100%? The one's you mentioned would not agree with you 100% either.