I would be leaving that leaf to produce energy for the plant to grow its quickest. Even though you may think that leaf is "shading" the branch underneath, that branch is relying on that leaf to make energy so that the branch can grow at its quickest. Removing the leaf will just reduce your plants ability to produce energy and slow your plants growth. In 2-3 days time, the branch will emerge from under the leaf anyhow, so their really is no point to removing a perfectly healthy, green, energy producing leaf. The small leaves growing with the emerging branch can in no way produce nowhere near as much energy as the bigger leaf that you are wondering about removing. On top of all this, UV light which your plant needs to make energy, will actually pass through the upper leaf to strike the lower leaves, it is just that we as humans can not see this occurring with our naked eyes, so to therefore think that somehow the leaf/new branch underneath is missing out, is incorrect/not possible. It will however miss out on energy to grow, if you do remove the big, green, healthy, energy producing leaf. It is my recommendation that only yellow leaves are to be removed from any cannabis plant, for once they are yellow, they have served their purpose. Also, cannabis being the fantastically designed plant that it is, will also store/accumulate starches, sugars, amino acids etc in her leaves, for a ready supply of these vital growth elements when she enters flowering. It is far more efficient for the flowering plant to draw upon these "stored" elements in her leaves during flowering than it is to manufacture them at the same time as an energy intensive activity such as flower formation. This is one vital fact the defoliation brigade fail to understand, de-leafing not only reduces the plants ability to produce energy, thus actually slowing growth, it also robs the plant of this fantastic store of vital growth elements. It is basic plant biology 101! Here endeth the sermon.
Have a look at my diaries and see how plants grow when they have never had healthy green leaves removed. I certainly can't notice any slowed growth due to "shaded bud sites"
Hope this helps,....
Organoman.