how far is 1/2 way through, In my most recent grow i cut / cleared about 25% of my lower growth out with no issue 3 weeks into flower but honestly it's ALWAYS a risk to stress your plant out during flower and i should have done it during veg. So with all of that yes it could benefit your main "sinks" to get rid of the other sinks that are under producing. However you could also stress the plant and make it hermie or stress it out enough to slow the growth and production.
Long story short there is a risk and a reward here, so decide for yourself if it's worth it because you are the one taking the risk, in my opinion though i would clear it out.