Thanks Greg..
Through my entire career w/ Local 3 I never made a fixture whip longer than 6ft.That was drilled into our heads from day one. Now that I'm on my own & looking for some basis on the rule, I only see 6ft. max rule in 410.67 Special provisions for flush and recessed Luminares ..Also.. It seems the use of stranded conductors in the whip is mentioned in 410.28 for chain hung fixtures etc. I can't honestly say I have ever fed any drop in flourescent fixtures with solid wire. You learn something new everyday. I thank everyone for their responses...keep them coming!! Thanks again ToHo