Large fan leaves produce the energy the buds needs too grow. They do not pull energy away from the buds. Your logic is flawed and incorrect. Stoner logic at its best.
Thats ok if you think so. But there is plenty of information regarding this subject and very easy to access. Large fan leaves do initially provide resources for the plant, during veg phase and early bloom. During the bloom phase after initial flowering when the roots stop growing and the plants stop growing and stretching these big leaves are no longer needed the same way as they are during growth phase. The buds are formed and now they are going to bulken up and ripen. Removing these leaves will focus all the moisture, water and nutrients into swelling up the flowers and increasing bud development and size.
Thats the whole point of indoor growing systems such as hydroponics soilless constantly are being fed and thus you are feeding your roots and this is what gives your plant the nutrients and energy they need to grow and produce flowers. The first few weeks of bloom they do provide resources to grow and stretch and produce flowers same as the veg phase. Why do you think fan leaves fall and die off as harvest approaches? These leaves are no longer useful and they yellow and shrivel up fall off and die. If you simply remove these leaves after the 4-5 week or final 2 weeks of bloo, you will than understand how it works.
Research it and look it up.
Removing these leaves especially during final 2 weeks of bloom will not hurt your plants or fuck up your yield. It will increase your yield when done correctly. And also help them finish up and ripen for harvest including producing additional resins and trichomes.
Try it out and you will see. I promise this isnt something I am just making up. Theres alot alot alot of articles written about this, theres books written on it and many expert growers who all use these practices for their grows.