Like many other things with the immigration process there are no specific rules that cover this, not everything is covered by written rules. Many things are at the discretion of the officer handling the case. The information and advice that is given on this forum is from the past experience of forum members. Nobody is telling you what to do, that is up to you. We are just giving you information to help you an informed decision.
Do a search on here, you will hear the same thing mentioned hundreds of times.