this all depends on strain and the genes of the plant. also type of medium your using (nutes in soil already). some plants are more nute sensitive than others. you just have to increase the dosage slowly and see how each plant reacts.
i am using the foxfarm line-up. in round 1 some of my plants started to get a little nute burn at half strength every other watering.
i am in round 2 and giving them 1/4 strength every third watering and they seem to be doing great.
when using nutes less is more. so if your leaf tips are starting to burn, back off on the nutes.