Also, apical dominance is the primary reason why buds higher on the plant develop better and not how much light hits the flowers. Flower has 1/100th of the pigmentation of leaves. Very little photosynthesis occurs there. It is much more efficient that light hits leaves. The products of photosynthesis, primarly ATP and other sugars, are highly mobile. they enter the phloem and that sugary, nutrient rich liquid is ever-present throughout the plant, if fed well. Which areas take the most from the phloem is about apical dominance -- the same thing behind how plant trainingn works. Highest growth node takes the most resources, all other factors the same.
it is moer complicated by vascular tissue. obviously, primary branching will take more than secondary limbs and so forth
I've heard this urban myth for too long. The last 1.5 years i've been purposely pushing leaves over particular bud sites to compare to similar budsites of similar dominance. There is no difference from the shielded flower and the non-shielded flower of simialr dominance. Certainly nonw you can distinguish with the human eye. the products of photosynthesis are HIGHLY mobile and is continually pumped into the phloem.