I did in fact try that re: waiting a day in Diamond League and still got in a Diamond League with people who had ridiculous XP by Wednesday, before the week was even over. I've written off the achievement. :P

Yeah, even though I myself am an introvert, I've noticed that get-togethers with fellow introverts, unless you know them really well, tend to leave the new person feeling kind of excluded. It's part of why I don't people XD;