You need to be careful with R. v. Schlesinger that decision means nothing at an Ontario Court of Justice. JPs will not even hear it because it's not binding to their courts.
It's dangerous to compare Radar and Lidar (Laser), use them synonymously. They're both treated differently at the trial court level.
Caselaw requires Radar to be tested before and after use. If you read Appeal Court Decisions regarding the testing before and after, you'll see that it's only for "radar". D'Astous v. Baie-Comeau (Ville) (1992), 74 C.C.C. (3d) 73
However, Lidar (Laser) only needs to be tested based on the manufacturer's recommendation. Sometimes, in the manufacturer's manual they only state that the device needs to be tested "BEFORE" use.
Some officers do their due diligence, and conduct additional tests at the conclusion of their shift.
Keep in mind that R. v. Roshani-Kalkhoran leaves it up to the Justice of Peace to accept oral evidence (without notes of testing) that it's their usual practice to test the device before/after their shift.
None of this is a slam dunk, there's appeal decisions supporting both sides.