My opinion Having sectional control for both seed/dry fertilizer offsets any advantage that liquid fertilizer only sectional control might have.  Seed isn't cheap either especially pulse crops.  And yes we did equip one of our drills for liquid fertilizer and used it for a few years.  Didn't see much of a difference other then the higher cost for liquid plus it brings on its own set of problems just like dry fert.  There is no free ride.