Applying for Study Permit in Canada while on a Visit Visa

[Alwayssuccessful!]

Has anyone had the experience of applying for a study permit from within Canada while on a visit visa? I know as a general rule, you are required to leave the country and apply from your home country, if you are applying from within Canada, or alternatively, submit your application as though you are not in Canada. But my question is, in a situation where you have done your medicals in advance and have the records, your biometric information is already with CIC by virtue of your visit visa application, police certificate is with you (things that would normally require you to go back to your country to obtain them), has anyone ever been successful applying for study permit while on visit but with all the requirements?

Again, do you think this applicant would be required to at least return from the first visit before seeking a study permit? Is the fact the visitor has not made a return trip a huge factor in the study permit decision?