[admissionsguy]

5 years sounds low, as discussed there. Even starting with a physics degree background and this being my passion, I am giving myself 10 years to reach top standard in the sense of truly mastering every area.

I suspect the 5 years as a general reference timeframe refers to full-time students who study to be computationally competent and pass exams well, but lack deep understanding of the subject area, let alone ability to solve truly difficult or novel problems.

For someone with strong high school background following the standard academic path without any delay, it would take at least 3(bsc)+1-2(msc)+3(phd)+??(postdoc) years to become a truly independent theoretical physicist.