Just because the wife wants to is no reason to start second guessing equipment manuals. RVs are a little more complicated than what she is used to doing at home... and those differences should be recognized and respected. Not doing so will cost you money, plain and simple. In the case of short runs on an engine, it will build condensation that will not have sufficient time to dissipate because it is not coming up to operating temperature. On the other hand, eventually replacing a generator is way cheaper and easier than living with an unhappy wife. :)