You raise very good point. Somewhere this policy has loophole but its not flawless by 100%. Your point is if you can match your experience with choice of program and VO made positive decision based on that, but later you change and do something completely different, then thats where the loophole is.
Most change in immigration policies happens after certain number reached. Before you didnt need to apply for New SP from outside of Canada but now yes you do. It is because of the abuse of this policy that triggered that. I hope they are also paying attention and somehow they will change the policy. It contradicts with projection on future occupations demand