(a side point about definitions... "valid" is a word that has been so often used in widely varying ways that most don't even realize that it really ought to be used in fairly technical ways ...in legal documents ..."a valid title" ...or in logic to mean a conclusion which follows from certain premises. Thus, it is possible to have a 'valid' argument which is totally false.)

Valid shouldn't be used to just mean 'okay' or 'acceptable'.