I think stinkyattic means that because they are using Organic Soil Additives/Soil Amendments (eg Bat or Sea Bird Guano etc) that are active within the grow mediumn they will find it diffucult to flush those Nutes out. These Organic Soil Amendments/Additives are constanlty being broken down in the soil. It is not possible to dilute these additives because they are physically withing the grow medium and not exclusively added via irrigation.

A Nutrient or Fertiliser consist of elements that are chemically available to the plant once added via irrigation. There is no time spent breaking down compounds. This means that if you add too much Fertiliser you can dilute that over concentration in the soil by flushing with ph balanced water and/or a very very dilute/light bloom/nute (say 10-20% of recommended dose) feed.