No. Commissioning and training are productive work and cannot be performed on a visitor entry. File early, use premium processing where available, and schedule the line's start-up after approval.
The line waits for the approval notice, not the other way round
Hypothetical example: the U.S. subsidiary's blending line is mechanically complete and customers expect product in eight weeks. The company should file immediately with the complete evidence, request premium processing where available for the classification, and accept that a request for evidence would pause the clock. Meanwhile the chemist may visit to attend meetings and inspect the installation, but she may not run trial batches, validate product or train staff on a visitor admission; doing so is unauthorized employment and puts the petition and her future admissions at risk. If the customer deadline cannot move, the subsidiary can contract a U.S. chemist for preliminary equipment checks that require no proprietary knowledge and reserve the formulation work for her arrival. Once approved she is admitted at a port of entry as a Canadian citizen with the approval notice. Build the production schedule around the approval date, and tell customers a realistic date rather than a hopeful one.
Hypothetical example: a desalination-equipment calibration specialist is needed for a commissioning window, but her former employer has not returned the employment verification. That record can settle the required one qualifying year abroad within the three years before filing or admission, so the company should not substitute an unsupported résumé. File only after the corporate and knowledge evidence agree. L-1B time has a five-year maximum; the project plan should reserve enough status for later troubleshooting instead of assuming every extension will be available.