What is needed in the organisation is a system for students to record instructor differences.
Get the students to record what the difference is and who told them to do it that way. Exaplain that it is no relection on them but it ensures that instructors can get together and decide a common approach to the issue. If it really is a case of the student making it up then they will avoid naming the instructor or the instructor will clarify their misunderstanding.
Reasons for turning off the landing light at the hold on a light aircraft;
Avoid glare for other pilots on approah or lining up from the other side;
Increase bulb life and avoid overheating (reduced cooling airflow);
Reduced drain on the battery at low RPM where the alternator having just started the aircraft after some serious cranking is doing it's best to power nav lights, radios, internal lights etc while also being required to try and charge the battery.
At night on a grass airfield the landing light will not show creep forward until a speed has been acheived........better idea not to point at anything (point between the taxi lights) in the first place.
Checklists as others have said are not procedure lists or do lists. Learn the procedure but use the checklist after to check that the essential requirements have been carried out.
Finally what does this say about the two organisations (assuming that Flying For Fun is not a sole operator/CFI in his own organisation):
Flying For Fun: Well, I will do exactly what I'd like my students to do - take on board all opinions, and then decide which works best for me.....
or
The Baron: At my club we advocate.......
Regards,
DFC