What does "in good health" mean with respect to Canadian entry?

According to the Canadian government's basic guidance on visitor visas, the "Basic travel requirements" for traveling to Canada are (my emphasis):

have a valid travel document, like a passport

be in good health

have no criminal or immigration-related convictions

convince an immigration officer that you have ties—such as a job, home, financial assets or family—that will take you back to your home country

convince an immigration officer that you will leave Canada at the end of your visit
have enough money for your stay.

The amount of money you will need depends on how long you will stay and if you will stay in a hotel, or with friends or relatives.

Similarly, a page on inadmissibility mentions "you have a serious health problem" as a reason for being refused admission, but does not define what constitutes a serious health problem versus a non-serious health problem (that, logically, would not result in inadmissibility to Canada).

A more detailed page specifies that persons may be refused entry or a visa on...

health grounds – if their condition is likely to:
endanger public health or public safety, or

cause excessive demands on health or social services (some exceptions exist 2 3)

Still, no actual guidance is provided on when exactly a health problem is serious enough to trigger refusal.

What is the definition of "in good health" as it relates specifically to entering Canada? I'm guessing that a cold, a broken arm, a hernia, or athlete's foot isn't enough to result in entry refusal, but how serious does a condition have to be?

Is it based on formal diagnosis (e.g. there is a list of diagnoses that are per se deemed to "endanger public health or public safety" and a list of diagnoses that are not)?
Does the CBSA official make an independent judgment of a person's overall health and whether that person is likely to need "excessive" services?
Is there a specific dollar amount that constitutes excessive (e.g. officials are supposed to refuse you entry if your medical bills for the previous 12 months were over $10,000)?

There is a procedure for obtaining an officially recognized Medical Exam, but not all visitors to Canada are required to obtain one. I'm more asking the question with reference to these visitors.

This is not a request for advice - I've never been refused entry to Canada on health grounds or warned that I might be. I'm just curious as to what the actual rule is and thought that it would be helpful for people who might not be in such great health to know as well. E.g. is this requirement really just a way to protect Canada from major threats like Tuberculosis and Ebola, or are people actually getting turned away at the border for arthritis and varicose veins?