No... Medicals is mandatory, I was a bit confused with your earlier post, if you have not received your medical examination request but received a mail from CIC that your passport is dispatched, then most likely it might not be a good news....
However, in many cases, CIC sends the passport back to the applicant and requests them to do the medicals and return the passport again for VISA stamping.
So, keep your fingers crossed and stay positive.
Do let us know what happened.
Good luck.