Several points. First, C-24 is more complex than you write here. This is the text:
Bill C-24 also adds the requirement that permanent residents seeking citizenship intend to reside in Canada once citizenship is granted (new section 5(1)(c.1)), a stipulation contained in the 1947 Canadian Citizenship Act. Permanent residents can fulfill this criterion when abroad through the employment of their spouse, common-law partner or parent – or their own employment – in service to Canada as defined in new sections 5(1.01) and 5(1.02). New section 5(1.1) provides that the permanent resident’s intention must be continuous from the date of his or her application until he or she has taken the oath of citizenship.
Note the word 'continuous' -- how are you going to have a continuous intent to reside in Canada, if you are planning to leave for four years as you apply? In fact, you are applying with the expressed intent to leave.
Secondly, you're not a citizen of Canada -- so, by dictating the conditions under which you can apply for citizenship, Canada is not controlling its citizens. It's controlling the conditions under which PRs get to become citizens.
Third, Expedited Processing is for situations in which a PR requires Canadian citizenship to do something, such as take a job with the Federal government. Why do you need Canadian citizenship to study outside of Canada?
