There are times when i really want some cases and then i just refresh the windows for new ones for a while too. In that time can usualy open one in few seconds at most.
Opening something fast doesn't necesary mean macro.
I've seen many taken fast by Holic, but i also got some before him too.
If u want a bit safer cases just reserve your new level up slots to active randoms instead of people with high sed and high sed friends.