This is NOT an attempt to 'find ways around the law', it is an attempt to think about it in a practical manner to understand what the lawmakers are aiming to achieve.
The law makers were aiming to achieve that the PIC must make
provision for flight to an alternate aerodrome, when required, in accordance with the following paragraphs. (AIP 73.1.1) That is all, no interpretation needed.
One other point (not claiming its conclusive) is the CAR definition of an alternate: "alternate aerodrome means an aerodrome specified in the flight plan".
"Centre VXX flight plan amendment". Flight plans don't just happen on the ground.