The immigration department actively encourages you to file applications on your own at the links Do I need to use an immigration representative for my citizenship application? , as well as Do I need a representative to help me apply? . Further, one of the main documents submitted in applications, at the link http://www.cic.gc.ca/english/pdf/kits/forms/IMM5476E.pdf states, “You do not need to hire a representative, it is your choice”.
Based on the above, it is fair to say that the immigration department is doing as much as possible to discourage you from hiring a representative, by emphasizing that the choice is yours, as well as providing most of the forms on the website Citizenship and Immigration Canada | Citoyenneté et Immigration Canada.
However, what may make one hesitant to self-file an application under Express Entry, is the fact that a refusal would affect any future application to enter Canada, and indeed, with increased information sharing, may affect one’s ability to enter other English speaking countries.
The frustration those experience filing documents for the stage after Express Entry, namely, the Invitation To Apply, is well documented at ” Express Entry Permanent Residence program is anything but . ”
Part of the immigration department’s mandate is to use discretion to keep people out of Canada as well as let them into Canada. The ‘keeping out’ part overlaps with enforcement arms of the government like the Canada Border Services Agency. Given the broad mandate, it would be inappropriate to rely in the immigration department exclusively for advice.
Taken as a whole the above risks and difficulties would reasonably lead one to think carefully about filing an application under Express Entry on their own.