“Two Stop Sign Infractions But One Ticket?”

Hmm, that's interesting. In Ontario, our Provincial Offences Act makes no reference to the Criminal Code, except to say that it replaces the summary conviction procedures in the Criminal Code: "The purpose of this Act is to replace the summary conviction procedure for the prosecution of provincial offences, including the provisions adopted by reference to the Criminal Code (Canada), with a procedure that reflects the distinction between provincial offences and criminal offences." (Provincial Offences Act (Ontario), section 2(1)).

But for Saskatchewan, it seems that the summary conviction procedures from the Criminal Code do apply in combination with your province's Summary Offences Procedure Act: "Subject to this Act, any other Act or any regulation, proceedings to enforce an Act, regulation or bylaw by fine, penalty or imprisonment may be brought summarily before a justice under the summary conviction provisions of the Criminal Code, as amended from time to time." (Section 4(1))

Since there is a different legislative framework between our two provinces, I can only really comment about how it works in Ontario.