There's so much surface water on the gel itself, and the sugar content makes it slightly hygrophilic (water-attracting), so what ends up happening, is large enough colonies may "mine" the gel for water, licking up any available water and nutrients as they get deeper.
Some ants also feed the bits that don't have available surface moisture to brood. Formula Blue 100 and Aqua 300 are best used as a gel, while Green 600 makes no difference, as it doesn't contain protein.
I've found the gel to be the most convenient for all my colonies, which vary considerably by development from test tube-stage, to larger colonies. 1 cc of liquid is far too little to measure reliably (the amount the silicone mold breaks up into little 1cc cubes), and so less product tends to be wasted when feeding the gel, even if the ants don't eat most of it.