When ready to advance technologically, I use to try and bottom down the science slider so I barely make the discovery next round. I even do that 2-3 rounds before the discovery in order to check my progress. Typically during the last round I reduce my scientists and turn them into tax collectors up to the point that my last scientist precisely disovers the technology and one less scientist means that I will not make the discovery that round. My assumption is that extra science bottles get lost when a discovery is made, so it is better to get some cash, but is this assumption correct?