Keeping your options open is also known as indecision. In many, if not most, cases, committing to something - and necessarily foregoing other things - creates the highest probability of having impact.
I note with interest that Cal, having chosen academia over a career in the "real world", seems to have become an expert in gaming academia in itself, its tests and admission hurdles, etc. There's nothing necessarily wrong with that; many people need a college degree for their own ends, and may be helped by what Cal provides. But navigation of the academe is not a large niche, not large enough to avoid making choices for. So the value of following the Cal's rule here is far from self-evident.
I know some very smart people who, when faced with a choice, didn't choose, and now find themselves somewhat rudderless, in their early 30s, still not knowing what to do and surprised at how late in the day it's gotten.
Making a choice doesn't usually preclude you from changing direction if you find, after investing your time and effort, that it's not working out. But delaying all choice is very rarely the right option. There's no good reason to think that time spent choosing will increase your feeling of certainty in what you choose.
I note with interest that Cal, having chosen academia over a career in the "real world", seems to have become an expert in gaming academia in itself, its tests and admission hurdles, etc. There's nothing necessarily wrong with that; many people need a college degree for their own ends, and may be helped by what Cal provides. But navigation of the academe is not a large niche, not large enough to avoid making choices for. So the value of following the Cal's rule here is far from self-evident.