OK - I stand corrected regarding the certification issue when referring specifically to the Lear 45.
However - I stand by my comment that the Operating Manual should be followed. If pilots feel the need to "band-aid" procedures and checklists (based on personal experience/preference) without endorsement from the OEM, scope exists for larger and larger deviations to occur as time goes on. This problem is often common among small operations with no significant standards department.
Having faced similar discrepancies (between the Limitations Chapter and Operating Procedures) before, I can say that Bombardier were receptive to the suggestion of a correction and it was done with appropriate process. Having said that, I do believe that Bombardier manuals are far from consistent in many areas.
If an accident occurred in the takeoff or landing phase, even if it was unrelated to the lack of yaw damper, I for one would not like to explain why I was contravening the Operating Manual, perhaps risking my job or the insurance.
Raising concerns with the OEM via the appropriate channels is one of our responsibilities as professional aviators.
VI