But, did you not notice this (on the first page):
Maintaining legal status
Spouses and common‑law partners of Canadian citizens and permanent residents in Canada who wish to apply for permanent resident status are no longer required to have legal immigration status provided that they have an eligible sponsor. All other eligibility requirements continue to apply.
There's also this:
(from publication ip08):
5.27. Legal temporary resident status in Canada
Under the current Regulations, applicants in this spouse or common-law partner in Canada class
must have a valid temporary resident status on the date of application and on the date they
receive permanent resident status to be eligible to be members of the class.
However, under the spousal policy, applicants who lack status as defined under the public policy
(see “What is lack of status under the public policy” below) may be granted permanent residence
so long as they meet all the other requirements of the class (i.e., they are not inadmissible for
reasons other than “lack of status.”)
However, applicants who do not have temporary resident status and who cannot be granted
positive consideration under the public policy can be removed at any time. Further, the spousal
policy does not change the requirement to seek necessary authorization to visit Canada or to
work or study here.