Will rinsing water down conical flask during titration affect final result?
I do not believe this is true. Once you add an amount of reactant into your flask adding more water will not change the number of moles of reactant that are present in the flask. The titrant will react in the mole ratio for that particular reaction so water doesn’t play a role. You can rinse the flask and even use water to get part of a drop into your flask for a more accurate titration.