So I am currently in the process of applying for PhD programmes in the UK having completed a MSc already. I completed my masters outside of the Top 5 and in the Top 10. I am applying for PhD programmes in a few of the Top 10 but assuming I get admitted to a programme within the Top 6 - 10 universities, which generally administer a 1+3 programme (1 year of courseworks and 3 years of research), I was just wondering if it's possible (and how to) independently learn rigorous technical skills needed for a good PhD and future job prospects? For example, (and this is entirely anecdotal evidence) that students with UK PhD's in the Top 10 often confine themselves to a single niche with a weak understanding of other disciplines. For example, if was to specialise in Growth Theory, I would still want to be able to engage with the Macroeconomic literature on DSGE models and macroeconometrics. I say this within the context of US PhD's being far stronger because of there 2+4 year systems.
I understand that time inherently constrains my ability to do so but if I allocate x amount of hours per week to focusing on improving technical skills, will this fair me well enough?