It all depends what the plant looks like. Usually i grow mines short n bushy by topping n training.(defoliating also keeps em shorter) I take off any leaf blocking light to a lower site. However, Some plants(single cola, non bushy)may not benefit at all from defoliation because theres not enough sites down there to catch the light goin that way.
Comprendes?
The fan leaf is a satellite and nutrient provider for the shoot its connected to(and partially to the whole plant as well) Wait til this shoot has leaves of its own big enough to provide it own food, then you can procede to cut its fan leaf.