In the case of soluble nutrients: More often. To keep levels high in a steady manor, but not so high that it damages the root system.
The issue with stronger solutions is that it can damage the roots and cause bacterial blooms in the soil that produce too much CO2 in the root system and screw up the pH. Stick with the recommended dosage, but use it twice as often. But also, use your brain. A nutrient mixture that has a 'once per year' dosage could be 100x more concentrated than something with a 'use every other watering' on the label.
With pelletized organic fertilizer, I double the dose. But I've tried and tested those amounts and I'm sure they don't cause issues. Better to dose a bit on the lower side than to kill a tree in a gamble.