Pacing of big projects is essential to future big science successes. Multi-billion dollar projects increasingly will end up in the too-tough-to-sell pile. But big projects can be viewed as several smaller projects that can be allocated to various expertise centers. And then each center can itself spawn smaller projects. The pace of new projects must be rapid enough that work for new science PhDs is always available. The pace should not be so rapid that there was insufficient time to analyze all prior data in the subject area.
Interspersing big projects with smaller related projects could further guarantee that we wring out all possible existing knowledge before launching another big project, eliminating costly false starts and misdirection. An important decision in starting a new big science project is the availability of appropriate support technology. If a new technology will be available in a couple of years that would save a significant percentage of total costs, why not wait those extra years?