I go with budsites as well but I don't have any scientific argument for it....am going with what I have always heard.

One interesting note which may make no sense at all: If the fan leaves need the light more how come the budsites not exposed to lighting don't grow as well even though the fan leaves connected to them get plenty of lighting since they seem to be the largest (usually budsites more toward the bottom of plant with the super-sized fan leaves)