I donot believe in cleansing etc.We are all children of god.But I understand the principle that if non hindus enter the temple,they might go out and condemn the very same god they had visited.Since it is not correct on anyone's part to enter a temple and blame the god,allowing people with a written statement that they would never do blasphemy would be a correct thing to do.
But cleansing a temple because someone from another faith entered the temple is as grave as untouchability.Who knows who brings milk to the temple and who feeds the cows used for getting milk. religious untouchability is as grave as untouchability against the lower classes. Its time that the priests realise that times have changed and a brahmin is going abroad while a dalit might be praying to lord rama and being very pious.
There is no measure to how good or bad a person is,and caste/religion does not determine it.