You should not trim fan leaves if you want a healthy plant that produces big buds
those leaves are what makes the bud,,,,,,,,,,,,period
without them there is bud that will not be there for you to smoke
others will tell you to trim, you will get lots of different opinions
but in the end it is all about how much you expect from the plant and those big leaves are the engine that makes the plant grow
and while you see shade or what looks like no light getting thru, please remember the plant does not have eyes can't see shade and "perceives" light differently than we do, there is elements of needed light that are getting thru
But as I said it is up to you to decide how you will grow as well as what opinions you accept or believe???