Or put simply, 3-year vs. 5-year PhD?
Many programmes in UK (and EU) take up 3 years, as opposed to a minimum of 4-5 years in North America. For a masters degree holder, with a goal to stay in academia, is a 3-year Ph.D. too short to prepare one for postdocs and academic roles? Or would the extra year(s) in a 5-year programme be a repetition of the masters?
Is the short duration enough in preparing an academic and his/her career? While the additional year(s) in a longer programme costly and dispensable? This question is informed by the many discussions here and elsewhere lamenting the competitiveness and difficulty of staying in academia, especially in the UK. I am asking from a UK/EU point of view (more specifically, social science), as I am not sure if this (potentially unwarranted) concern is generalizable in other countries and disciplines.